Construction and operation of electric or hybrid aircraft

ABSTRACT

This disclosure describes at least embodiments of an aircraft monitoring system for an electric or hybrid airplane. The aircraft monitoring system can be constructed to enable the electric or hybrid aircraft to pass certification requirements relating to a safety risk analysis. The aircraft monitoring system can have different subsystems for monitoring and alerting of failures of components, such as a power source for powering an electric motor, of the electric or hybrid aircraft. The failures that pose a greater safety risk may be monitored and indicated by one or more subsystems without use of programmable components.

RELATED APPLICATIONS

Any and all applications for which a foreign or domestic priority claimis identified in the Application Data Sheet of the present applicationare hereby incorporated by reference under 37 CFR 1.57.

FIELD OF THE DISCLOSURE

The present disclosure is related to vehicles, such as electric orhybrid aircraft.

BACKGROUND

Electric and hybrid vehicles have become increasingly significant forthe transportation of people and goods. Such vehicles can desirablyprovide energy efficiency advantages over combustion-powered vehiclesand may cause less air pollution than combustion-powered vehicles duringoperation.

Although the technology for electric and hybrid automobiles hassignificantly developed in recent years, many of the innovations thatenabled a transition from combustion-powered to electric-poweredautomobiles unfortunately do not directly apply to the development ofelectric or hybrid aircraft. The functionality of automobiles and thefunctionality of aircraft are sufficiently different in many aspects sothat many of the design elements for electric and hybrid aircraft mustbe uniquely developed separate from those of electric and hybridautomobiles.

Moreover, any changes to an aircraft's design, such as to enableelectric or hybrid operation, also require careful development andtesting to ensure safety and reliability. If an aircraft experiences aserious failure during flight, the potential loss and safety risk fromthe failure may be very high as the failure could cause a crash of theaircraft and pose a safety or property damage risk to passengers orcargo, as well as individuals or property on the ground.

The certification standards for electric or hybrid aircraft are furtherextremely stringent because of the risks posed by new aircraft designs.Designers of aircraft have struggled to find ways to meet thecertification standards and bring new electric or hybrid aircraftdesigns to market.

In view of these challenges, attempts to make electric and hybridaircraft commercially viable have been largely unsuccessful. Newapproaches for making and operating electric and hybrid aircraft thuscontinue to be desired.

SUMMARY

Flying an aircraft such an airplane can be dangerous. Problems with theaircraft may result in injury or loss of life for passengers in theaircraft or individuals on the ground, as well as damage to goods beingtransported by the aircraft or other items around the aircraft.

In order to attempt to mitigate potential problems associated with anaircraft, numerous organizations have developed certification standardsfor ensuring that aircraft designs and operations satisfy thresholdsafety requirements. The certification standards may be stringent andonerous when the degree of safety risk is high, and the certificationstandards may be easier and more flexible when the degree of safety riskis low.

Such certification standards have unfortunately had the effect ofslowing commercial adoption and production of electric or hybridaircraft. Electrical hybrid aircraft may, for example, utilize newaircraft designs relative to traditional aircraft designs to account fordifferences in operations of electric or hybrid aircraft versustraditional aircraft. The new designs however may be significantlydifferent from the traditional aircraft designs. These differences maysubject the new designs to extensive testing prior to certification. Theneed for extensive testing can take many resources, time andsignificantly drive up the ultimate cost of the aircraft.

The present disclosure provides simplified, yet robust, components andsystems for an electric powered aircraft that simplify and streamlinecertifications requirements and reduce the cost and time required toproduce a commercially viable electric aircraft. The present disclosureprovides multiple components and systems that can be mixed and matchedaccording to aircraft needs and requirements. Accordingly, althoughmultiple different components are described below, the components orsystems are not required to be all used together in a single embodiment.Rather, each component or system can be used independent of the othercomponents or systems of the present disclosure.

The aircraft can be designed so that different subsystems of theaircraft are constructed to have a robustness corresponding to theirresponsibilities and any related certification standards, as well aspotentially any subsystem redundancies. Where a potential failure of theresponsibilities of a subsystem would likely be catastrophic (forexample, resulting in fatalities on the ground of individuals not in theaircraft, such as when an aircraft suddenly losses altitude), thesubsystem can be designed to be very simple and robust and thus may beable to satisfy difficult certification standards. The subsystem, forexample, can be composed of non-programmable, non-stateful components(for example, analog or non-programmable combinational logic electroniccomponents) rather than a processor. The subsystem, for example, canactivate indicators such as lights rather than more sophisticateddisplays. The subsystem thus may not be affected by software orprogramming bugs and may be less impacted by external interference, suchas voltage spikes, electromagnetic interference, or radiation, which maycause a malfunction. On the other hand, where either (i) a subsystem ofan aircraft monitors a parameter redundantly with another subsystem ofthe aircraft that is composed of non-programmable, non-statefulcomponents or (ii) a potential failure of the responsibilities of asubsystem would likely be less than catastrophic (for example, result inhazardous, major, minor, or no safety effect), the subsystem can be atleast partly digital and designed to be more complicated, feature-rich,and easier to update and yet able to satisfy associated certificationstandards. The subsystem can, for instance, include a programmablecomponent or a stateful component like a processor that outputs andpresents information on a sophisticated display. This can desirablyenable the aircraft to maintain feature-rich systems without sacrificingrobust, easily-certifiable safety systems. Although a programmablecomponent or a stateful component may be difficult to safely andreliably update and the programmable component may be more prone to amalfunction due to voltage spikes, electromagnetic interference, orradiation than non-programmable, non-stateful components, theprogrammable component or the stateful component can more easily providefunctionality which may be difficult to provide with non-programmable,non-stateful components.

The aircraft may be provided with a battery monitoring subsystemresponsible for determining, for example, the health of batterycomponents. If battery components were to overheat and catch fire, theaircraft would likely suffer a catastrophic failure and rapid loss ofaltitude. The battery monitoring subsystem thus can be constructedentirely of non-programmable, non-stateful components. The batterymonitoring subsystem can, for instance, include one or more temperaturesensors that detect the temperature proximate one or more batteries inthe aircraft and output a signal responsive to detection of atemperature that exceeds a threshold indicative of an unsafe condition.The signal can in turn be hardwired to a light or a speaker in thecockpit of the aircraft to indicate the over-temperature condition to apilot of the aircraft.

A separate power management subsystem may be incorporated with theaircraft to, for example, monitor battery life. The power managementsystem can be responsible for monitoring and displaying an amount ofenergy remaining for powering an aircraft and can be constructed of aprocessor that outputs a graphical user interface or speaker. The powermanagement subsystem need not be made of non-programmable, non-statefulcomponents at least because the aircraft includes the battery monitoringsubsystem which also monitors the health of the battery components.Thus, one monitoring system can be made of non-programmable,non-stateful components (such as, analog or non-programmablecombinational logic electronic components) to monitor catastrophicfailures, while one or more feature-rich processors, sequential logicelectronic components, or programmable combinational logic electroniccomponents of another monitoring system can provide additionalcatastrophic or other non-catastrophic monitoring of aircraft systems.

A redundant subsystem in an aircraft can desirably enable certainfeatures of the aircraft to continue to be available even though asubsystem that is primarily responsible for the certain features may beinoperable. Moreover, the redundant subsystem can be secondarilyresponsible for the certain features without the subsystem that isprimarily responsible for those features providing status or controlinformation to the redundant subsystem. This can be beneficial, forexample, in the event that the primary system suddenly fails. Thesecondary system can take over without the need for a handoff.

An aircraft in accordance with the disclosure herein can includemultiple subsystems each capable of performing the responsibilities ofone or more other of the multiple subsystems. For example, a firstsubsystem of the aircraft may be tasked with primary responsibility formanaging a first set of tasks of the aircraft while a second subsystemof the aircraft may be tasked with secondary responsibility for thefirst set of tasks. Similarly, the second subsystem may be tasked withprimary responsibility for a second set of tasks of the aircraft whilethe first subsystem may be tasked with secondary responsibility for thesecond set of tasks. If one of the first subsystem or the secondsubsystem is inoperative, the other of the first subsystem or the secondsubsystem can take over responsibility for the inoperative subsystem. Ashared recorder may additionally store data that can be received by thefirst subsystem and the second subsystem from one or more aircraftcomponents so that the first subsystem and the second subsystem may takeover primary responsibility for one or more tasks based at least on thedata stored to the shared recorder and without communication of statusinformation or operating instructions between the first subsystem andthe second subsystem. The first subsystem and the second subsystem caneach be different instances of similar or the same computer hardware orsoftware and the control features of the first subsystem and the secondsubsystem may be selectively activated or inactivated to enable primaryor secondary control.

A motor of an aircraft can include multiple field coils. Each of themultiple field coils may be used to drive the motor during differentphases of rotation for the motor. During use or over the life of themotor, however, one or more of the individual field coils can fail,which may cause a dramatic decrease in average power output by themotor.

To address the failure of one or more field coils of the motor, thecontroller of the aircraft can adjust its driving of at least some ofthe other field coils to compensate for the failure of the one or morefield coils. For instance, the controller can drive the functioningfield coils of the motor so that an average power output of the motorremains unchanged despite the failure of the one or more field coils orso that a decrease in average power output caused by the failure of theone or more field coils is reduced. The controller may provide greatercurrent to some functioning field coils causing the instantaneous poweroutput of the motor to increase during certain phases of rotation inorder to make up for the failed coil(s).

An aircraft in accordance with the disclosure here may have featuresthat improve the usability or operability of the aircraft.

An aircraft and its components can have different power needs atdifferent times. At takeoff, the aircraft may consume a relativelysignificant amount of power for a short period of time to start movingthe aircraft and bring the aircraft off the ground. At cruising altitudeand speed, the aircraft may consume a relatively less significant amountof power over a longer period of time to maintain a consistent speed andaltitude.

To flexibly satisfy the power needs of an aircraft, the aircraft caninclude different power supplies having different characteristics forsupplying power to the same components of the aircraft at differenttimes or the same time. The different power supplies can have differentenergy capacities or different power output capacities from one anotherand may be connected so that the different power supplies can pass powerto each other. The different power supplies may, for example, bedifferent batteries having battery cells with different energy or poweroutput capacities.

Moreover, the aircraft can include one or more motors that are able tooperate as a generator to charge the one or more different powersupplies. One of the different power supplies can be used to drive theone or more motors while another of the different power supplies may besimultaneously charged by the one or more motors. This arrangement canbe desirable, for example, because a charging power supply can chargefrom a supplying power supply without including additional circuitry andincreasing the aircraft weight to otherwise facilitate charging of thecharging power supply from the supplying power supply.

An electric or hybrid aircraft also poses a challenge for storing,monitoring, and utilizing numerous battery cells. The battery cells maytogether represent a significant amount of weight and take up asignificant amount of space in the electric or hybrid aircraft. Thebattery cells can additionally pose a serious safety risk, such as inthe event of fire or failure, and thus should be carefully managed.Different electric or hybrid aircraft may also have different physicaldesigns and different power requirements that can influence the desiredconfigurations of the battery cells for the different aircraft.

An aircraft in accordance with the disclosure herein can be poweredusing a modular battery system. The modular battery system can includemultiple battery modules that may be physically connected. The batterycell modules can each include a module housing that supports multiplebattery cells electrically connected in parallel with one another by aconductive plate and that may be connected to one or more modulehousings of other battery cell modules. The module housings can beshaped and sized so that the module housings can be coupled together andto fit a particular aircraft design or placement of the module housingsin various parts of the aircraft. The multiple battery modules canfurther be connected in series with one another to form a power sourcefor the aircraft that has a greater output voltage.

An aircraft monitoring system for an electric or hybrid airplane isdisclosed. The aircraft monitoring system can be constructed to enablethe electric or hybrid aircraft to pass certification requirementsrelating to a safety risk analysis. The aircraft monitoring system canhave different subsystems for monitoring and alerting of failures ofcomponents of the electric or hybrid aircraft, and the failures thatpose a greater safety risk can be monitored and indicated by one or moresubsystems without use of programmable components. The aircraftmonitoring system can include a first subsystem and a second subsystem.The first subsystem can be supported by a housing and consist ofnon-programmable components. The housing can fly and be propelled by anelectric motor. The non-programmable components can monitor a powersource supported by the housing and output a first alert to notify of afirst condition associated with the power source. The power source canpower the electric motor, and the first condition can be likely toimminently cause a fatality or a destruction of the housing. The secondsubsystem can be supported by the housing and include a processor and acommunication bus. The processor can monitor the power source fromcommunications on the communication bus and output a second alert tonotify of a second condition associated with the power source.

The aircraft monitoring system of the preceding paragraph can includeone or more of the following features: The non-programmable componentscan consist of analog or combinational logic electronic components. Thenon-programmable components can consist of non-stateful components. Anysubsystem that is supported by the housing and configured to notify ofcatastrophic conditions can monitor for the catastrophic conditions andnotify of the catastrophic conditions without using programmablecomponents or stateful components, and the catastrophic conditions beinglikely to imminently cause the fatality or the destruction of thehousing. The non-programmable components can activate an indicatorsupported by the housing to output the first alert, and the indicatorcan remain inactive unless the indicator is outputting the first alert.The indicator can include a light or an audible alarm. The firstsubsystem may not control the power source, and the second subsystem cancontrol the power source. The first subsystem can process analog signalsand binary signals but may not multivalued digital signals. The aircraftmonitoring system can include multiple printed circuit boards, and atleast part of the first subsystem and at least part of the secondsubsystem can be mounted on the multiple printed circuit boards. Thefirst subsystem may not communicate via the communication bus. Thenon-programmable components can monitor the power source using a firstoutput from a first sensor, and the processor can monitor the powersource using a second output from a second sensor different from thefirst sensor. The first sensor and the second sensor can detect a stateof the power source. The first sensor and the second sensor can measurea temperature of the power source. The first sensor and the secondsensor can detect an undervoltage condition, an overvoltage condition,an underpressure condition, an overpressure condition, an undercurrentcondition, an overcurrent condition, an excessive internal resistancecondition, a low internal resistance condition, a high temperaturecondition, or a low temperature condition of the power source. The firstsensor and the second sensor can detect that the power source is onfire. The non-programmable components can output the first alert to theprocessor or another processor supported by the housing, and theprocessor or the another processor can activate a component supported bythe housing to attempt to address the first condition. Thenon-programmable components can output the first alert to an electronicdevice remote from the housing. The non-programmable components and theprocessor can monitor the power source using a common output from asensor. The second alert can indicate that an amount of energy stored bythe power source is below a threshold. The power source can include abattery. The first condition can be a failure or an overheating of thepower source. The first condition can be the power source being on fire.The first alert can indicate that a crash of the housing is imminent.The non-programmable components can include an electronic deviceconfigured to process an analog signal. The aircraft monitoring systemcan include a display configured to present the second alert.

A method of operating an aircraft monitoring system of an electric orhybrid airplane is disclosed. The aircraft monitoring system can beconstructed to enable the electric or hybrid aircraft to passcertification requirements relating to a safety risk analysis. Themethod can include: supporting a first subsystem and a second subsystemwith a housing, the first subsystem consisting of non-programmablecomponents, the second subsystem comprising a processor and acommunication bus, the housing being configured to fly and be propelledby an electric motor; powering, by the power source, the electric motor;monitoring, by the non-programmable components, a power source supportedby the housing; outputting, by the non-programmable components, a firstalert to notify of a first condition associated with the power source,the first condition being likely to imminently cause a fatality or adestruction of the housing; monitoring, by the processor, the powersource from communications on the communication bus; and outputting, bythe processor, a second alert to notify of a second condition associatedwith the power source.

The method of the preceding paragraph can include one or more of thefollowing features: The method can include activating an indicatorsupported by the housing to output the first alert, inactivating theindicator when the non-programmable components are not outputting thefirst alert, and presenting the second alert on a display supported bythe housing. The non-programmable components monitor the power sourceusing a first output from a first sensor, and the processor monitors thepower source using a second output from a second sensor. The method caninclude, by the first sensor and the second sensor, detecting anundervoltage condition, an overvoltage condition, an underpressurecondition, an overpressure condition, an undercurrent condition, anovercurrent condition, an excessive internal resistance condition, a lowinternal resistance condition, a high temperature condition, or a lowtemperature condition associated with the power source. The method caninclude, responsive to the first alert, activating a component supportedby the housing to attempt to address the first condition.

A power management system for a vehicle is disclosed. The powermanagement system can include batteries that have different energydensity and power density battery cells from one another and that areusable for selectively powering a transducer of the vehicle at differenttimes and for charging one another. The power management system caninclude a first battery, a second battery, and electronic circuitry. Thefirst battery can power a transducer supported by a housing. Thetransducer can propel the housing. The second battery can power thetransducer and charge the first battery. The second battery can includelower energy density battery cells and higher power density batterycells than the first battery. The electronic circuitry can controlwhether one or both of the first battery or the second battery powersthe transducer.

The power management system of the preceding paragraph can include oneor more of the following features: The electronic circuitry can controlwhen the second battery charges the first battery. The electroniccircuitry can cause the second battery to charge the first battery whilethe first battery is powering the transducer. The electronic circuitrycan cause the second battery to charge the first battery while the firstbattery is not powering the transducer. The power management system caninclude a supercapacitor configured to charge the first battery. Theelectronic circuitry can cause the supercapacitor to charge the firstbattery. The electronic circuitry can control whether the supercapacitorpowers the transducer. The transducer can charge the supercapacitor. Thepower management system can include a converter that may convert firstelectrical current from the first battery into second electrical currentto charge the second battery. The first battery or the second batterycan include Li-Ion or Li-Po battery cells. The electronic circuitry caninclude a controller. The transducer can charge the first battery or thesecond battery. The power management system can include a commutatorthat may determine whether the transducer is charging either the firstbattery or the second battery. The power management system can includeanother transducer on a common axis as and mechanically coupled to thetransducer, and the another transducer can charge the first battery orthe second battery while the transducer propels the housing. Theelectronic circuitry can generate a drive signal to operate thetransducer.

A method of operating a power management system of a vehicle isdisclosed. The method can include: powering, by a first battery, atransducer supported by a housing; powering, by a second batterycomprising lower energy density battery cells and higher power densitybattery cells than the first battery, the transducer; propelling, by thetransducer, the housing; and controlling, by electronic circuitry,whether one or both of the first battery or the second battery powersthe transducer.

The method of the preceding paragraph can include one or more of thefollowing features: The method can include powering, by asupercapacitor, the transducer; and controlling, by the electroniccircuitry, whether the supercapacitor powers the transducer. The methodcan include charging, by the transducer, the first battery or the secondbattery. The method can include generating, by the electronic circuitry,a drive signal to operate the transducer.

A power management system for a vehicle having one or more transducersis disclosed. The power management system can include a first battery, asecond battery, and electronic circuitry. The first battery can power afirst transducer supported by a housing. The first transducer can propelthe housing. The second battery can power a second transducer supportedby the housing. The second transducer can propel the housing and chargethe second battery. The electronic circuitry can cause the first batteryto power the first transducer while the second transducer charges thesecond battery.

The power management system of the preceding paragraph can include oneor more of the following features: The first transducer and the secondtransducer can be the same transducer. The first transducer can includea rotor, a first set of windings, and a second set of windings, and thefirst set of windings can be usable to drive the rotor from the firstbattery and the second set of windings can be usable to charge thesecond battery. The first transducer and the second transducer can bemechanically coupled to one another. The first transducer and the secondtransducer can be different transducers. The electronic circuitry canoperate the first transducer or the second transducer in multiple modes,and the multiple modes can include a first mode in which the firsttransducer is powered by the first battery and not the second battery.The multiple modes can include one or more of a second mode in which thefirst transducer is powered by the first battery and the second battery,a third mode in which the first transducer is powered by the secondbattery and not the first battery, a fourth mode in which the firsttransducer is powered by the first battery and the second transducer ischarging the second battery, a fifth mode in which the first transduceris charging the first battery and the second transducer is powered bythe second battery, a sixth mode in which the first transducer ischarging the first battery and the second battery is not charging orpowering, a seventh mode in which the second transducer is charging thesecond battery and the first battery is not charging or powering, or aneighth mode in which the first transducer is charging the first batteryand the second transducer is charging the second battery. The powermanagement system can include a supercapacitor, and the multiple modescan include one or more of a ninth mode in which the first transducer orthe second transducer is powered by the supercapacitor, a tenth mode inwhich the first transducer or the second transducer is powered by thesupercapacitor and the first battery or the second battery, an eleventhmode in which the first transducer is powered by the first battery, thesecond transducer is powered by the second battery, and the firsttransducer or the second transducer is charging the supercapacitor, antwelfth mode in which the first transducer or the second transducer ischarging the supercapacitor, and a thirteenth mode in which the firsttransducer or the second transducer is charging the supercapacitor andthe first battery or the second battery. The second battery can includelower energy density battery cells and higher power density batterycells than the first battery. The power management system can include asupercapacitor. The electronic circuitry can include power thetransducer from the first battery, the second battery, and thesupercapacitor. The first transducer can charge the first battery, thesecond battery, or the supercapacitor. The supercapacitor can charge thefirst battery or the second battery. The electronic circuitry caninclude one or more controllers. The electronic circuitry can generate adrive signal to operate the first transducer or the second transducer.

A method of operating a power management system of a vehicle isdisclosed. The method can include: powering, by a first battery, a firsttransducer supported by a housing; powering, by a second batterydifferent from the first battery, a second transducer supported by thehousing; propelling, by the first transducer, the housing; propelling,by the second transducer, the housing; and charging, by the secondtransducer, the second battery while the first battery powers the firsttransducer.

The method of the preceding paragraph can include one or more of thefollowing features: The first transducer and the second transducer canbe the same transducer. The first transducer can include a rotor, afirst set of windings, and a second set of windings, and the chargingcan include charging, by the second set of windings, the second batterywhile the first battery drives the rotor via the first set of windings.The method can include mechanically coupling the first transducer to thesecond transducer.

A power management system for a vehicle having an electric motor isdisclosed. The power management system can include a first power source,a second power source, and electronic circuitry. The first power sourcecan power an electric motor supported by a housing. The electric motorcan propel the housing. The second power source can power the electricmotor and, when the first power source is powering the electric motor,charge from the electric motor; the electronic circuitry can cause thefirst power source to power the electric motor while the electric motorcharges the second power source. The electric motor can include a rotor,a first set of windings, and a second set of windings, and the first setof windings can be usable to drive the rotor from the first power sourceand the second set of windings can be usable to charge the second powersource from the rotor.

An operation management system for a vehicle is disclosed. The operationmanagement system can include a first subsystem and a second subsystemdifferent from the first subsystem. Each of the first subsystem and thesecond subsystem can control multiple components using bus data receivedon a communication bus. Multiple components can be supported by ahousing and include a first component and a second component. Thehousing can be propelled by a motor that is powered by a power source.The first subsystem can manage operations of the first component and,when the second subsystem is not operational, manage operations of thesecond component. The second subsystem can manage the operations of thesecond component and, when the first subsystem is not operational,manage the operations of the first component.

The operation management system of the preceding paragraph can includeone or more features: When the first subsystem is not operational, thesecond subsystem can begin managing the operations of the firstcomponent without the first subsystem communicating operation data aboutthe first component to the second subsystem. In the event of a failureof the first subsystem when the first subsystem is managing theoperations of the first component, the second subsystem canautomatically begin managing the operations of the first component. Thefirst component can include the motor, and the second component caninclude the power source. The first component can include the powersource, and the second component can include the motor. The firstsubsystem can execute the same computer software instructions as thesecond subsystem. The first subsystem can include a different instanceof the same computer hardware as the second subsystem. The operationmanagement system can include a recorder configured to store the busdata, and the first subsystem and the second subsystem can receive thebus data from the recorder rather than from other components that areconfigured to transmit the bus data via the communication bus. The busdata can include operation data about the first component or the secondcomponent. The bus data can include a state of the first component orthe second component, a temperature of the first component or the secondcomponent, or an undervoltage condition or an overvoltage condition ofthe first component or the second component. The power source comprisesa battery. The operation management system can include one or moresensors configured to transmit the bus data via the communication bus.

A method of making or using the operation management system of thepreceding two paragraphs is disclosed.

A control system for a vehicle motor that includes multiple field coilsis disclosed. The control system can include a memory device and acontroller. The memory device can store an operating parameter. Thecontroller can vary, according to the operating parameter, an electricalcurrent provided to individual field coils of multiple field coils of amotor to compensate for a failure of one or more of the multiple fieldcoils and maintain a power output of the motor despite the failure ofthe one or more of the multiple field coils. The multiple field coilscan generate a torque on a rotor of the motor. The motor can besupported by a housing and propel the housing.

The control system of the preceding paragraph can include one or more ofthe following features: The controller can vary a rotation rate of themotor or a pitch of a propeller supported by the housing to compensatefor the failure of the one or more of the multiple field coils andmaintain the power output despite the failure of the one or more of themultiple field coils. The controller can: prior to a failure of a firstfield coil of the multiple field coils, provide the electrical currentone time to all of the multiple field coils in an order prior toproviding the electrical current another time to any of the multiplefield coils; and subsequent to the failure of the first field coil, nolonger provide the electrical current to the first field coil. Thecontroller can, subsequent to the failure of the first field coil,increase the electrical current provided to at least some of themultiple field coils to compensate for the failure of the first fieldcoil. The controller can, subsequent to the failure of the first fieldcoil, increase the electrical current provided to a second field coiland a third field coil of the multiple field coils. The first field coilcan be before the second field coil and after the third field coil inthe order. A sensor can detect the failure of the one or more of themultiple field coils. The sensor can detect the failure of the one ormore of the multiple field coils from a temperature, an electricalcurrent, or a magnetic field measured by the sensor. The controller canno longer provide the electrical current to a first field coil of themultiple field coils in response to detecting the failure of the firstfield coil. The controller can set the operating parameter responsive toan output from the sensor. The controller can vary the electricalcurrent provided to the individual field coils to compensate for thefailure of at least two of the multiple field coils. The controller canvary the electrical current provided to the individual field coils tocompensate for the failure of at least three of the multiple fieldcoils. The controller can modulate power input to the motor over time tocompensate for the failure of the one or more of the multiple fieldcoils. The controller can, during a modulation cycle for the motor,increase the power input to one or more functioning field coils of themultiple field coils to compensate for the failure of the one or more ofthe multiple field coils. The controller can maintain the power outputof the motor above a threshold despite the failure of the one or more ofthe multiple field coils. The operating parameter can indicative ofwhich of the one or more of the multiple field coils have failed. Themotor can be an electric motor.

A method of operating a motor of a vehicle is disclosed. The method caninclude: supporting, by a housing, a motor; providing an electricalcurrent to individual field coils of a multiple field coils of a motorto generate a torque on a rotor of the motor; propelling, by the motor,the housing; and varying the electrical current provided to theindividual field coils of the multiple field coils to compensate for afailure of one or more of the multiple field coils and maintain a poweroutput of the motor despite the failure of the one or more of themultiple field coils.

The method of the preceding paragraph can include one or more of thefollowing features: The method can include varying a rotation rate ofthe motor or a pitch of a propeller supported by the housing tocompensate for the failure of the one or more of the multiple fieldcoils and maintain the power output despite the failure of the one ormore of the multiple field coils. The varying can include, subsequent tothe failure of a first field coil of the multiple field coils,increasing the electrical current provided to at least some of themultiple field coils to compensate for the failure of the first fieldcoil. The method can include detecting, by a sensor, the failure of theone or more of the multiple field coils. The power output of the motorcan be maintained above a threshold despite the failure of the one ormore of the multiple field coils.

A modular power system for an electric or hybrid airplane is disclosed.The modular power system can include a power source configured to powera motor and including a multiple battery modules. The motor can propel avehicle housing that is configured to fly. The multiple battery modulescan include a first battery module and a second battery module. Thefirst battery module can include a first module housing, multiple firstbattery cells, and a first plate. The first module housing can supportthe multiple first battery cells, and the multiple first battery cellscan be electrically connected in parallel with one another at least bythe first plate. The second battery module can include a second modulehousing, multiple second battery cells, and a second plate. The secondmodule housing can support the multiple second battery cells and becoupled to the first module housing. The multiple second battery cellscan be electrically connected in parallel with one another at least bythe second plate and electrically connected in series with the multiplefirst battery cells.

The modular power system of the preceding paragraph can include one ormore of the following features: The first plate can distribute heatevenly across the multiple first battery cells so that the multiplefirst battery cells age at a common rate. The first battery module canbe cooled by air. The first plate can include copper. The multiple firstbattery cells can include 16 battery cells. Each of at least some of themultiple first battery cells can be substantially shaped as a cylinder.The first module housing can be substantially shaped as a rectangularprism. The first module housing can include plastic. The first modulehousing can prevent a fire in the multiple first battery cells fromspreading outside of the first module housing. The modular power systemcan include one or more sensors that monitor a voltage or a temperatureof individual battery cells of the plurality of first battery cells. Thepower source can be electrically isolated by galvanic isolation fromanother power source configured to power the motor. The first batterymodule may not be electrically isolated by galvanic isolation from thesecond battery module. The power source can have an output voltage lessthan 120 V. The power source can have a maximum power output between 1kW and 60 kW during operation. The power source can have a maximumvoltage output between 10 V and 120 V during operation. The power sourcehas a maximum current output between 100 A and 500 A during operation. Afirst side of the first module housing can couple to the second modulehousing, and a second side of the first module housing opposite thefirst side can couple to a third module housing that supports aplurality of third battery cells. The first module housing and thesecond module housing can be sized and shaped to fit between structuralsupports of the vehicle housing when the first module housing is coupledto the second module housing. The first module housing and the secondmodule housing can be sized and shaped to fit within a wing of thevehicle housing when the first module housing is coupled to the secondmodule housing. The first module housing and the second module housingcan be sized and shaped to fit within an engine compartment of the wingwhen the first module housing is coupled to the second module housing.The first module housing and the second module housing each can have anouter length, an outer width, and an outer height that each range from30 mm to 250 mm. The outer length, the outer width, and the outer heighteach can range from 50 mm to 100 mm. The first battery module and thesecond battery module can be electrically coupled in series withmultiple additional battery modules. A total number of battery modulesincluded in the plurality of additional battery modules can adjust toscale a size or an output of the power source. One or more of the firstbattery module, the second battery module, or the multiple additionalbattery modules can be disconnected to reduce a size or an output of thepower source.

A modular power system for an electric or hybrid airplane is disclosed.The modular power system can include a power source configured to powera motor and including multiple battery modules. The motor can propel avehicle housing that is configured to fly, the multiple battery modulesincluding a first battery module and a second battery module. The firstbattery module can include a first module housing and a plurality offirst battery cells. The first module housing can support the multiplefirst battery cells and have a first outer length, a first outer width,and a first outer height ranging from 30 mm to 250 mm. The secondbattery module can include a second module housing and multiple secondbattery cells. The second module housing can support the multiple secondbattery cells and coupled to the first module housing. The second modulehousing can have a second outer length, a second outer width, and asecond outer height each ranging from 30 mm to 250 mm. The secondbattery cells can be electrically connected in parallel with one anotherand electrically connected in series with the multiple first batterycells.

A method of making or using the modular power system of the precedingthree paragraphs is disclosed.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A illustrates an aircraft, such as an electric or hybrid aircraft;

FIG. 1B illustrates a simplified block diagram of an aircraft;

FIG. 2 illustrates management systems for operating an aircraft;

FIG. 3 illustrates an aircraft monitoring system;

FIGS. 4 and 5 illustrate implementations of battery monitoring systems;

FIGS. 6 and 7 illustrate implementations of master circuits formonitoring battery monitoring systems;

FIGS. 8, 9, 10, 11, 12, and 13 illustrate schematic views ofimplementations of a power management system;

FIGS. 14A and 14B illustrate a battery module usable in an aircraft;

FIGS. 15A and 15B illustrate a power source formed of multiple batterymodules;

FIG. 16 illustrates multiple power sources arranged and connected forpowering an aircraft;

FIGS. 17A and 17B illustrate multiple power sources positioned in a noseof an aircraft for powering the aircraft;

FIGS. 18A and 18B illustrate multiple power sources positioned in a wingof an aircraft for powering the aircraft;

FIG. 19 illustrates a motor with multiple field coils; and

FIG. 20 illustrates a process for operating a motor to compensate forfailure of a field coil of the motor.

DETAILED DESCRIPTION

System Overview

FIG. 1A illustrates an aircraft 100, such as an electric or hybridaircraft, and FIG. 1B illustrates a simplified block diagram of theaircraft 100. The aircraft 100 includes a motor 110, a management system120, and a power source 130. The motor 110 can be used to propel theaircraft 100 and cause the aircraft 100 to fly and navigate. Themanagement system 120 can control and monitor of the components of theaircraft 100, such as the motor 110 and the power source 130. The powersource 130 can power the motor 110 to drive the aircraft 100 and powerthe management system 120 to enable operations of the management system120. The management system 120 can include one or more controllers aswell as other electronic circuitry for controlling and monitoring thecomponents of the aircraft 100.

FIG. 2 illustrates components 200 of an aircraft, such as the aircraft100 of FIGS. 1A and 1B. The components 200 can include a powermanagement system 210, a motor management system 220, and a recorder230, as well as a first battery pack 212A, a second battery pack 212B, awarning panel 214, a fuse and relay 216, a converter 217, a cockpitbattery pack 218, a motor controller 222, one or more motors 224, and athrottle 226.

The power management system 210, the motor management system 220, andthe recorder 230 can monitor communications on a communication bus, suchas a controller area network (CAN) bus, and communicate via thecommunication bus. The first battery pack 212A and the second batterypack 212B can, for instance, communicate on the communication busenabling the power management system 210 to monitor and control thefirst battery pack 212A and the second battery pack 212B. As anotherexample, the motor controller 222 can communicate on the communicationbus enabling the motor management system 220 to monitor and control themotor controller 222.

The recorder 230 can store some or all data communicated (such ascomponent status, temperature, or over/undervoltage information from thecomponents or other sensors) on the communication bus to a memory devicefor later reference, such as for reference by the power managementsystem 210 or the motor management system 220 or for use introubleshooting or debugging by a maintenance worker. The powermanagement system 210 and the motor management system 220 can eachoutput or include a user interface that presents status information andpermits system configurations. The power management system 210 cancontrol a charging process (for instance, a charge timing, currentlevel, or voltage level) for the aircraft when the aircraft is coupledto an external power source to charge a power source of the aircraft,such as the first battery pack 212A or the second battery pack 212B.

The warning panel 214 can be a panel that alerts a pilot or anotherindividual or computer to an issue, such as a problem associated with apower source like the first battery pack 212A. The fuse and relay 216can be associated with the first battery pack 212A and the secondbattery pack 212B and usable to transfer power through a converter 217(for example, a DC-DC converter) to a cockpit battery pack 218. The fuseand relay 216 can protect one or more battery poles of the first batterypack 212A and the second battery pack 212B from a short or overcurrent.The cockpit battery pack 218 may supply power for the communication bus.

The motor management system 220 can provide control commands to themotor controller 222, which can in turn be used to operate the one ormore motors 224. The motor controller 222 may further operate accordingto instructions from the throttle 226 that may be controlled by a pilotof the aircraft. The one or more motors can include an electricbrushless motor.

The power management system 210 and the motor management system 220 canexecute the same or similar software instructions and may perform thesame or similar functions as one another. The power management system210, however, may be primarily responsible for power managementfunctions while the motor management system 220 may be secondarilyresponsible for the power management functions. Similarly, the motormanagement system 220 may be primarily responsible for motor managementfunctions while the power management system 210 may be secondarilyresponsible for the motor management functions. The power managementsystem 210 and the motor management system 220 can be assignedrespective functions, for example, according to system configurations,such as one or more memory flags in memory that indicate a desiredfunctionality. The power management system 210 and the motor managementsystem 220 may include the same or similar computer hardware.

The power management system 210 can automatically perform the motormanagement functions when the motor management system 220 is notoperational (such as in the event of a rebooting or failure of the motormanagement system 220), and the motor management system 220 canautomatically perform the power management functions when the powermanagement system 210 is not operational (such as in the event ofrebooting or failure of the power management system 210). Moreover, thepower management system 210 and the motor management system 220 can takeover the functions from one another without communicating operationdata, such as data about one or more of the components being controlledor monitored by the power management system 210 and the motor managementsystem 220. This can be because both the power management system 210 andthe motor management system 220 may be consistently monitoringcommunications on the communication bus to generate control information,but the control information may be used if the power management system210 and the motor management system 220 has primary responsibility butnot if the power management system 210 and the motor management system220 does not have primary responsibility. Additionally or alternatively,the power management system 210 and the motor management system 220 mayaccess data stored by the recorder 230 to obtain information usable totake over primary responsibility.

System Architecture

Electric and hybrid aircraft (rather than aircraft powered duringoperation by combustion) have been designed and manufactured fordecades. However, electric and hybrid aircraft have still not yet becomewidely used for most transport applications like carrying passengers orgoods.

This failure to adopt may be in large part because designing an aircraftthat is sufficiently safe to be certified by certification authoritiesmay be very difficult. The certification of prototypes may moreover notbe sufficient to certify for commercial applications. Instead, acertification of each individual aircraft and its components may berequired.

This disclosure provides at least some approaches for constructingelectric powered aircraft from components and systems that have beendesigned to pass certification requirements so that the aircraft itselfmay pass certification requirements and proceed to active commercialuse.

Certification requirements can be related to a safety risk analysis. Acondition that may occur with an aircraft or its components can beassigned to one of multiple safety risk assessments, which may in turnbe associated with a particular certification standard. The conditioncan, for example, be catastrophic, hazardous, major, minor, or no safetyeffect. A catastrophic condition may be one that likely results inmultiple fatalities or loss of the aircraft. A hazardous condition mayreduce the capability of the aircraft or the operator ability to copewith adverse conditions to the extent that there would be a largereduction in safety margin or functional capability crew physicaldistress/excessive workload such that operators cannot be relied upon toperform required tasks accurately or completely or serious or fatalinjury to small number of occupants of aircraft (except operators) orfatal injury to ground personnel or general public. A major conditioncan reduce the capability of the aircraft or the operators to cope withadverse operating condition to the extent that there would be asignificant reduction in safety margin or functional capability,significant increase in operator workload, conditions impairing operatorefficiency or creating significant discomfort physical distress tooccupants of aircraft (except operator), which can include injuries,major occupational illness, major environmental damage, or majorproperty damage. A minor condition may not significantly reduce systemsafety such that actions required by operators are well within theircapabilities and may include a slight reduction in safety margin orfunctional capabilities, slight increase in workload such as routineflight plan changes, some physical discomfort to occupants or aircraft(except operators), minor occupational illness, minor environmentaldamage, or minor property damage. A no safety effect condition may beone that has not effect on safety.

An aircraft can be designed so that different subsystems of the aircraftare constructed to have a robustness corresponding to theirresponsibilities and any related certification standards, as well aspotentially any subsystem redundancies. Where a potential failure of theresponsibilities of a subsystem would likely be catastrophic, thesubsystem can be designed to be simple and robust and thus may be ableto satisfy difficult certification standards. The subsystem, forinstance, can be composed of non-programmable, non-stateful components(for example, analog or non-programmable combinational logic electroniccomponents) rather than programmable components (for example, aprocessor, a field programmable gate array (FPGA), or a complexprogrammable logic device (CPLD)) or stateful components (for example,sequential logic electronic components) and activate indicators such aslights rather than more sophisticated displays. On the other hand, whereeither (i) a subsystem of an aircraft monitors a parameter redundantlywith another subsystem of the aircraft that is composed ofnon-programmable, non-stateful components or (ii) a potential failure ofthe responsibilities of a subsystem would likely be less thancatastrophic, the subsystem can be at least partly digital and designedto be complicated, feature-rich, and easier to update and yet able tosatisfy associated certification standards. The subsystem can, forinstance, include a processor that outputs information to asophisticated display for presentation.

In some implementations, some or all catastrophic conditions monitoredfor by an aircraft can be monitored for with at least one subsystem thatdoes not include a programmable component or a stateful componentbecause certifications for programmable components or statefulcomponents may demand statistical analysis of the responsiblesubsystems, which can be very expensive and complicated to certify. Suchimplementations can moreover be counterintuitive at least because anelectric or hybrid aircraft may include one or more relatively advancedprogrammable or stateful components to enable operation of the electricor hybrid aircraft, so the inclusion of one or more subsystems in theaircraft that does not include any programmable components or anystateful components may be unexpected because the one or more relativelyadvanced programmable or stateful components may be readily and easilyable to implement the functionality of the one or more subsystems thatdoes not include any programmable components or any stateful components.

An aircraft monitoring system can include a first subsystem and a secondsubsystem. The first subsystem can be supported by an aircraft housingand include non-programmable, non-stateful components, such as analog ornon-programmable combinational logic electronic components. Thenon-programmable, non-stateful components can monitor a componentsupported by the aircraft housing and output a first alert to notify ofa catastrophic condition associated with the component. Thenon-programmable, non-stateful components can, for instance, activate anindicator or an audible alarm for a passenger aboard the housing tooutput the first alert. The indicator or audible alarm may remaininactive unless the indicator is outputting the first alert.Additionally or alternatively, the non-programmable, non-statefulcomponents can output the first alert to a computer aboard or remotefrom the aircraft (for example, to automatically trigger actions toattempt to respond to or address the catastrophic condition, such as tostop charging or activate a fire extinguisher, a parachute, or anemergency landing procedure or other emergency response feature) or anoperator of the aircraft via a telemetry system. The non-programmable,non-stateful components may, moreover, not be able to control thecomponent or at least control certain functionality of the component,such as to control a mode or trigger an operation of the component.

The second subsystem can be supported by the aircraft housing andinclude a processor (or another programmable or stateful component), aswell as a communication bus. The processor can monitor the componentfrom communications on the communication bus and output a second alertto notify of a catastrophic condition or a less than catastrophiccondition associated with the component. The processor can, forinstance, activate an indicator or audible alarm for a passenger aboardthe housing to output the second alert. Additionally or alternatively,the processor can output the second alert to a computer aboard or remotefrom the aircraft (for example, to automatically trigger actions toattempt to address the catastrophic condition, such as to activate afire extinguisher, a parachute, or an emergency landing procedure) or anoperator of the aircraft via a telemetry system. The processor maycontrol the component. The non-programmable, non-stateful components ofthe first subsystem additionally may not be able to communicate via thecommunication bus.

An example of such a design and its benefits are next described in thecontext of battery management systems. Notably, the design can beadditionally or alternatively applied to other systems of a vehicle thatperform functions other than battery management, such as motor control.

Battery Management Example

Battery packs including multiple battery cells, such as lithium-ioncells, can be used in electric cars, electric aircraft, and otherelectric self-powered vehicles. The battery cells may be connected inseries or in parallel to deliver an appropriate voltage and current.

Battery cells in battery packs can be managed and controlled by batterymanagement systems (BMS). A BMS can be a circuit that manages arechargeable battery cell by controlling its charging and dischargecycles, preventing it from operating outside its safe operating area,balancing the charge between cells, or the like. BMS can also monitorbattery parameters, such as the temperature, voltage, current, internalresistance, or pressure of the battery cell, and report anomalies. BMScan be provided by various manufacturers as discreet electroniccomponents.

Damage to battery cells can be very serious incidents that may causefire, explosions, or interruption of the powered circuit. Therefore, anydamage to a battery in a vehicle, such as an electric airplane, maydesirably be reported immediately and reliably to the pilot or driver ofthe vehicle. A reliable monitoring of battery cells by BMS can becritical for the safety of electric airplanes.

However, BMS can have failings in rare occurrences that cause problemswith battery cells which may not be reported correctly. For example, anovervoltage or overtemperature condition can, in some situations, affectnot only a battery cell, but also its BMS, so that the failure of thebattery cell is either not detected or not reported correctly. Even ifthe BMS functions correctly, a connecting bus between the BMS and thecockpit might be defective and prevent warning signals from beingtransmitted.

In order to prevent this risk, battery cells can be monitored with asecond, redundant BMS. If both BMS are of the same type, a defect orconception flaw that affects one BMS may also affect the redundant BMSas well, so that the gain in reliability can be limited. The presentdisclosure provides at least approaches to increase the reliability ofthe detection of malfunctions of battery cells in an electric vehicle,such as an electric aircraft. Redundant monitoring of parameters of eachbattery cell can be performed with two different circuits. Because asecond, redundant monitoring circuit may include non-programmable,non-stateful components rather than processors, sequential logicelectronic components, or programmable combinational logic electroniccomponents, its certification can be easier, and its reliability may beincreased. For example, because the second, redundant circuit may beprocessorless, may not include any sequential or programmablecombinational logic electronic components, and may not rely on anysoftware (for example, executable program code that is executed by aprocessor), its certification is made easier than if the second,redundant circuit relied on processors, sequential or programmablecombinational logic electronic components, or software.

The second, redundant monitoring circuit can provide for a redundantmonitoring of battery parameters and for a redundant transmission ofthose parameters, or warning signals depending on those parameters. Thesecond battery monitoring system may transmit analog or binary signalsbut not multivalued digital signals. The second battery monitoringcircuit may not manage the charge and discharge of battery cells, butinstead provide for monitoring of battery parameters, and transmissionof parameters or warning signals. Therefore, the second, redundantbattery monitoring circuit can be made simple, easy to certify, andreliable.

FIG. 3 illustrates a battery monitoring system. This system can be usedin an electric vehicle, such as an electric aircraft, a large size droneor unmanned aerial vehicle, an electric car, or the like, to monitor thestate of battery cells 1 in one of multiple battery packs and reportthis state or generate warning signals in case of dysfunctions.

The battery cells 1 can be connected in series or in parallel to delivera desired voltage and current. FIG. 3 shows serially connected batterycells. The total number of battery cells 1 may exceed 100 cells in anelectric aircraft. Each of the battery cells 1 can be made up ofmultiple elementary battery cells in parallel.

A first battery monitoring circuit can control and monitor the state ofeach battery cell 1. The first battery management circuit can includemultiple BMSs 2, each of the BMSs 2 managing and controlling one of thebattery cells 1. The BMSs 2 can each be made up of an integrated circuit(for instance, a dedicated integrated circuit) mounted on one printedcircuit board (PCB) of the PCBs 20. One of the PCBs 20 can be used foreach of the battery cells 1. FIG. 4 illustrates example components ofone of the BMSs 2.

The control of a battery cell can include control of its charging anddischarge cycles, preventing a battery cell from operating outside itssafe operating area, or balancing the charge between different cells.

The monitoring of one of the battery cells 1 by one of the BMSs 2 caninclude measuring parameters of the one of the battery cells 1, todetect and report its condition and possible dysfunctions. Themeasurement of the parameters can be performed with battery cellparameter sensors, which can be integrated in the one of the BMSs 2 orconnected to the one of the BMSs 2. Examples of such parameter sensorscan include a temperature sensor 21, a voltage sensor 22, or a currentsensor. An analog-to-digital converter 23 can convert the analog valuesmeasured by one or more of the parameter sensors into multivalueddigital values, for example, 8 or 16 bits digital parameter values. Amicrocontroller 24, which can be part of each of the BMSs 2, can comparethe values with thresholds to detect when a battery cell temperature,battery cell voltage, or battery cell current is outside a range.

The BMSs 2 as slaves can be controlled by one of multiple first mastercircuits 5. In the example of FIG. 3, each of the first master circuits5 can control four of the BMSs 2. Each of the first master circuits 5can control eight of the BMSs 2, or more than eight of the BMSs 2. Thefirst master circuits 5 can control more BMS and more battery cells inyet other implementations. The first master circuits 5 can be connectedand communicate over a digital communication bus 55.

The first master circuits 5 can also be connected to a computer 9 thatcollects the various digital signals and data sent by the first mastercircuits 5, and may display information related to the battery state andwarning signals on a display 13, such as a matrix display. The display13 may be mounted in the vehicle's cockpit to be visible by thevehicle's driver or pilot. Additionally or alternatively, the computer 9can output the information to a computer remote from the aircraft or tocontrol operations of one or more components of the aircraft asdescribed herein.

The BMSs 2 can be connected to the first master circuits 5 over adigital communication bus, such as a CAN bus. A bus driver 25 caninterface the microcontroller 24 with the digital communication bus andprovide a first galvanic isolation 59 between the PCBs 20 and the firstmaster circuits 5. In one example, the bus drivers of adjacent BMSs 2can be daisy chained. For example, as shown in FIG. 4, the bus driver 25is connected to the bus driver 27 of the previous BMS and to the busdriver 28 of the next BMS.

Each of the BMSs 2 and their associated microcontrollers can be rebootedby switching its power voltage Vcc. The interruption of Vcc can becontrolled by the first master circuits 5 over the digital communicationbus and a power source 26.

FIG. 6 illustrates example components of one of the first mastercircuits 5. The one of the first master circuits 5 can include a firstdriver 51 for connecting the one of the first master circuits 5 with oneof the BMSs 2 over the digital communication bus, a microcontroller 50,and a second driver 52 for connecting the first master circuits 5between themselves and with the computer 9 over a second digitalcommunication bus 55, such as a second CAN bus. A second galvanicisolation 58 can be provided between the first and second mastercircuits 5, 7 and the computer 9. The second galvanic isolation 58 can,for example, be 1500 VDC, 2500 Vrms, 3750 Vrms, or another magnitude ofisolation. The microcontroller 50, the first driver 51, and the seconddriver 52 can be powered by a powering circuit 53 and may be mounted ona PCB 54, one such PCB can be provided for each of the first mastercircuits 5.

FIG. 3 further illustrates a second battery monitoring circuit, whichcan be redundant of the first battery monitoring circuit. This secondbattery monitoring circuit may not manage the battery cells 1; forexample, the second battery monitoring circuit may not control charge ordischarge cycles of the battery cells 1. The function of the secondbattery monitoring circuit can instead be to provide a separate,redundant monitoring of each of the battery cells 1 in the batterypacks, and to transmit those parameters or warning signals related tothose parameters, such as to the pilot or driver or a computer aboard orremote from the aircraft as described herein. The second batterymonitoring circuit can monitor the state of each of the battery cells 1independently from the first battery monitoring circuit. The secondbattery monitoring circuit can include one of multiple cell monitoringcircuits 3 for each of the battery cells. The parameters or warningsignals may moreover, for example, be used by the second batterymonitoring circuit to stop charging (for instance, by opening a relay todisconnect supply of power) of one or more battery cells when the one ormore battery cells may be full of energy and a computer of the aircraftcontinues to charge the one or more battery cells.

FIG. 5 illustrates example components of one of the cell monitoringcircuits 3. Each of the cell monitoring circuits 3 can include multiplecell parameter sensors 30, 31, 32, 33 for measuring various parametersof one of the battery cells 1. The sensor 30 can measure a firsttemperature at a first location in one battery cell and detect anovertemperature condition; the sensor 31 can measure a secondtemperature at a second location in the same battery cell and detect anovertemperature condition; the sensor 32 can detect an undervoltagecondition in the same battery cell; and the sensor 33 can detect anovervoltage condition on the same battery cell. The undervoltagecondition can be detected, for example, when the voltage at the outputof one battery cell is under 3.1 Volts or another threshold. Theovervoltage condition might be detected, for example, when the voltageat the output of one battery cell is above 4.2 Volts or yet anotherthreshold. The thresholds used can depend, for instance, on the type ofbattery cell 1 or a number of elementary cells in the cell. Therefore,each or some of the sensors 30-33 can include a sensor as such and ananalog comparator for comparing the value delivered by the sensor withone or two thresholds, and outputting a binary value depending on theresult of the comparison. Other battery cell parameter sensors, such asan overcurrent detecting sensor, can be used in other implementations.

Various parameters related to one of the battery cells 1 can be combinedusing a combinational logic circuit 35, such as an AND gate. Thecombinational logic circuit 35 may not include programmable logic. Inthe example of FIG. 5, binary signals output by the sensors 30, 31, and32 are combined by a boolean AND gate into a single warning signal,which can have a positive value (warning signal) if and only if thetemperature measured by the two temperature sensors exceeds atemperature threshold and if the voltage of the cell is under a voltagethreshold. The detection of an overvoltage condition by the sensor 33,in the example of FIG. 5, may not combined with any other measure andcan be directly used as a warning signal.

The warning signals delivered by the combinational logic 35 or directlyby the parameter sensors 30-33 can be transmitted to a second mastercircuit 7 over lines 76, which can be dedicated and different from thedigital communication bus used by the first battery monitoring circuit.Optocouplers 36, 37, 38 provide a third galvanic isolation 60 betweenthe components 30-38 and the second master circuit 7. The third galvanicisolation 60 can provide the same isolation as the first galvanicisolation 59, such as 30V isolation, or the third galvanic isolation 60may provide a different isolation form the first galvanic isolation 59.

The sensors 30-33 and the combinational logic element 35 can be poweredby a powering circuit 34 that delivers a power voltage Vcc2. Thispowering circuit 34 can be reset from the second master circuit 7 usingan ON/OFF signal transmitted over the optocoupler 38.

The sensors 30-33 and the combinational logic element 35 can be mountedon a PCB. One such PCB can be provided for each of the battery cells 1.The sensors 30-33 and the combinational logic element 35 can be mountedon the same PCB 20 as one of the BMSs 2 of the first battery monitoringcircuit.

FIG. 7 illustrates example components of one of the second mastercircuits 7. In the example of FIG. 5, the one of the second mastercircuits 7 can include a combinational logic element 72, which may notinclude programmable logic, for combining warning signals, such asovertemperature/under-voltage warning signals uv1, uv2, . . . orovervoltage signals ov1, ov2, . . . from different battery cells intocombined warning signals, such as a general uv (undervoltage conditionin case of overtemperature) warning signal and a separate overvoltagewarning signal ov. Those warning signals uv, ov can be active when anyof the battery cells 1 monitored by the one of the second mastercircuits 7 has a failure. They can be transmitted over optocouplers 70,71 and lines 76 to the next and previous second master circuits 74, 75,and to a warning display panel 11 in the cockpit of the vehicle fordisplaying warning signals to the driver or pilot. The warning displaypanel 11 can include lights, such as light emitting diodes (LEDs), fordisplaying warning signals.

With the disclosed design of the cell monitoring circuits 3 and thesecond master circuits 7, no dormant alarms may remain undetected. Forexample, if a cable may be broken or a power supply is inactive, thewarning panel 11 can correctly show an alarm despite the broken cable orthe inactive power supply. This can be accomplished, for instance, byusing an inverted logic so that if the warning panel 11 does not receivea voltage or a current on an alarm line, an indicator may activate, butif the warning panel 11 does receive the voltage or the current on thealarm line, the indicator can deactivate.

The one of the second master circuits 7 can be mounted on a PCB. Onesuch PCB can be provided for each of the second master circuits 7. Oneof the second master circuits 7 can be mounted on the same PCB 54 as oneof the first master circuits 5 of the first battery monitoring circuit.

As can be seen, the second battery monitoring circuit can includeexclusively non-programmable, non-stateful components (such as, analogcomponents or non-programmable combinational logic components). Thesecond battery monitoring circuit can be processorless, and may notinclude any sequential or programmable combinational logic. The secondbattery monitoring circuit may not run any computer code or beprogrammable. This simplicity can provide for a very reliable secondmonitoring circuit, and for a simple certification of the second batterymonitoring circuit and an entire system that include the second batterymonitoring circuit.

The second battery monitoring circuit can be built so that any faultyline, components, or power source triggers an alarm. In one example, an“0” on a line, which may be caused by the detection of a problem in acell or by a defective sensor, line, or electronic component, can besignaled as an alarm on the warning panel; the alarm may only be removedwhen all the monitored cells and all the monitoring components arefunctioning properly. For example, if the voltage comparator ortemperature sensor is broken, an alarm can be triggered.

The computer 9, the display 13, and the warning display panel 11 in thecockpit can be powered by a power source 15 in the cockpit, which may bea cockpit battery and can be independent of other power sources used topower one or more other components.

Motor and Battery System

Battery packs including multiple battery cells, such as lithium-ioncells, can be used in electric cars, electric aircraft, and otherelectric self-powered vehicles. The battery cells can be connected inseries or in parallel to deliver an appropriate voltage and current.

In electrically driven aircraft, the battery packs can be chosen tofulfill the electrical requirements for various flight modes. Duringshort time periods like take off, the electrical motor can utilize arelatively high power. During most of the time, such as in the standardflight mode, the electrical motor can utilize a relatively lower power,but may consume a high energy for achieving long distances of travel. Itcan be difficult for a single battery to achieve these two powerutilizations.

The use of two battery packs with different power or energycharacteristics can optimize the use of the stored energy for differentflight conditions. For example, a first battery pack can be used forstandard flight situations, where high power output may not be demanded,but a high energy output may be demanded. A second battery pack can beused, alone or in addition to the first battery pack, for flightsituations with high power output demands, such as take-off maneuvering.

An electrical powering system can charge the second battery pack fromthe first battery pack. This can allow recharging of the second batterypack during the flight, subsequent to the second battery pack being usedin a high power output demanding flight situation. Therefore, the secondbattery pack can be small, which can save space and weight. In addition,this can allow different battery packs for different flight situationsthat optimize the use of the battery packs.

The electrical powering system can also charge the second battery packby at least one motor which works as generator (the motor may alsoaccordingly be referred to as a transducer). This can allow rechargingof the second battery pack during the flight or after the second batterypack has been used in a high power output demanding flight situation.Therefore, the second battery pack can be small, which can save spaceand weight. In addition, the different battery packs can allow therecovery of braking energy. Braking energy during landing or sinkingrecovered by a generator motor can create high currents which may not berecovered by battery packs used for traveling long distances. By using asecond battery pack suitable for receiving high power output in a shorttime, more braking energy can be recovered via the second battery packthan the first battery pack, for example.

The electrical powering system can also include a third battery pack,which includes a supercapacitor. Because supercapacitors can receive andoutput large instantaneous power or high energy in a short duration oftime, the third battery pack can further improve the electrical poweringsystem in some instances. A supercapacitor may, for example, have acapacitance of 0.1 F, 0.5 F, 1 F, 5 F, 10 F, 50 F, 100 F, or greater orwithin a range defined by one of the preceding capacitance values.

FIGS. 8 to 13 illustrate multiple electrical power systems.

FIG. 8 shows an electrical powering system that includes a first batterypack 91, a second battery pack 92, a circuit 90, and at least one motor94.

The first battery pack 91 and the second battery pack 92 can each storeelectrical energy for driving the at least one motor 94. The firstbattery pack 91 and the second battery pack 92 can have differentelectrical characteristics. The first battery pack 91 can have a higherenergy capacity per kilogram than the second battery pack 92, and thefirst battery pack 91 can have a higher power capacity (watt hours) thanthe second battery pack 92. Moreover, the first battery pack 91 can havea lower maximum, nominal, or peak power than the second battery pack 92;the first battery pack 91 can have a lower maximum, nominal, or peakcurrent than the second battery pack 92; or, the first battery pack 91can have a lower maximum, nominal, or peak voltage than the secondbattery pack 92. More than one or even all of the mentioned electricalcharacteristics of the first battery pack 91 and the second battery pack92 can be different. However, only one of the mentioned electricalcharacteristics may be different or at least one other characteristicthan the mentioned electrical characteristics may be different. Thefirst battery pack 91 and the second battery pack 92 can have the sameelectrical characteristics.

The type or the material composition of the battery cells of the firstbattery pack 91 and the second battery pack 92 can be different. Thetype or the material composition of the battery cells of the firstbattery pack 91 and the second battery pack 92 can be the same, but anamount of copper or an arrangement of conductors can be different. Inone example, the first battery pack 91 or the second battery pack 92 canbe a lithium-ion (Li-ion) battery or a lithium-ion polymer (Li-Po)battery. The second battery pack 92 may include a supercapacitor(sometimes referred to as a supercap, ultracapacitor, or Goldcap).

The first battery pack 91 can include relatively high energy-densitybattery cells that can store a high amount of watt-hours per kilogram.The first battery pack 91 can include low power battery cells. The firstbattery pack 91 can provide a DC voltage/current/power or can beconnected by a (two phase or DC) power line with the circuit 90.

The second battery pack 92 can include relatively low energy-densitybattery cells. The second battery pack 92 can include relatively highpower battery cells. The second battery pack 92 can provide a DCvoltage/current/power or is connected by a (two phase or DC) power linewith the circuit 90.

The first battery pack 91 can form an integrated unit of mechanicallycoupled battery modules or the first battery pack 91 may be anelectrically connected first set of battery modules. Similarly, thesecond battery pack 92 can form an integrated unit of mechanicallycoupled battery modules or the second battery pack 92 may be anelectrically connected second set of battery modules. Some or all of thebattery modules of each of first battery pack 91 or the second batterypack 92 can be stored in one or more areas of a housing of an aircraft,such as a within a wing or nose of the aircraft.

The first battery pack 91 can have a total energy capacity that exceedsa total energy capacity of the second battery pack 92. For example, aratio of the total energy capacity of the first battery pack 91 and thetotal energy capacity of the second battery pack 92 can be 2:1, 3:1,4:1, 5:1, 10:1, 20:1, 40:1, or 100:1 or within a range defined by two ofthe foregoing ratios.

The electrical powering system can include an external charginginterface for charging the first battery pack 91 or the second batterypack 92 when the aircraft is on the ground and connected to a chargingstation outside of the aircraft.

Each, some, or one of the at least one motor can be an electrical motor.The at least one motor 94 can be connected to the circuit 90. The atleast one motor 94 can receive over the circuit 90 electricalenergy/power from the first battery pack 91 or the second battery pack92 to drive the at least one motor 94. For example, the at least onemotor 94 can be a three phase motor, such as a brushless motor, which isconnected via a three phase AC power line with the circuit 90. However,the at least one motor 94 can instead be a different type of motor, suchas any type of DC motor or a one phase AC motor. The at least one motor94 can move a vehicle, such as an airborne vehicle like an aircraft. Theat least one motor 94 can drive a (thrust-generating) propeller or a(lift-generating) rotor. In addition, the at least one motor 94 can alsofunction as a generator. The electrical powering system or the at leastone motor 94 can include two or more electrical motors as describedfurther herein.

The different motors of the at least one motor 94 can have the same ordifferent characteristics. The at least one motor 94 can be a motor witha first set of windings connected with a first controller 96 and with asecond set of windings connected with a second controller 97, as shownfor example in FIG. 12. This can allow use of the at least one motor 94as generator and motor at the same time or to power the at least onemotor 94 from the first controller 96 and the second controller 97. Theat least one motor 94 can include a first motor 98 and a second motor 99as shown for example in FIGS. 11 and 13. The first and the second motor98 and 99 can be mechanically connected such that the rotors of thefirst and second motor 98 and 99 are mechanically coupled, for instancefor powering both the same propeller or rotor (as shown in FIGS. 11 and13). The first and the second motor 98 and 99 can, for example, drivethe same axis which rotates the propeller or rotor. However, the firstand second motor 98 and 99 may not be mechanically coupled and may drivetwo distinct propellers or rotors. The at least one motor 94 can includemore than two motors M1, M2, . . . Mi which are mutually connected, ormultiple mutually connected motors.

The circuit 90 can be connected with the first battery pack 91, thesecond battery pack 92, and the at least one motor 94.

The circuit 90 can include a controller 93 connected with the firstbattery pack 91, the second battery pack 92, and the at least one motor94. The controller 93 can, for example, be connected over a two phase orDC power line with the first battery pack 91 and the second battery pack92 or connected over a three phase power line with the at least onemotor 94. The controller 93 can transform, convert, or control the powerreceived from the first battery pack 91 or the second battery pack 92into motor driving signals for driving the at least one motor 94. Thecontroller 93 can include a power converter for converting the DCcurrent of the first battery pack 91 or the second battery pack 92 intoa (three phase) (AC) current for the at least one motor 94 (powerconverter working as inverter). The power converter can treat differentinput DC voltages (if the first battery pack 91 and the second batterypack 92 have different DC voltages). If the at least one motor 94 actsas generator, the power converter can convert the current generated fromeach phase of the at least one motor 94 into a DC current for loadingthe first battery pack 91 or the second battery pack 92 (power converterworking as rectifier). The controller 93 can create the motor drivingsignals for the at least one motor 94 based on user input.

The controller 93 can include more than one controller. The controller93 can include, for instance, a first controller 96 for powering the atleast one motor 94 from at least one of the first battery pack 91 andthe second battery pack 92 and a second controller 97 for powering theat least one motor 94 from at least one of the first battery pack 91 orthe second battery pack 92. The features described for the controller 93can apply to the first controller 96 or the second controller 97.Examples of such a circuit are shown in the FIGS. 10 to 13. In FIGS. 10to 12, the first controller 96 powers the at least one motor 94 from thefirst battery pack 91 and the second controller 97 powers the at leastone motor 94 from the second battery pack 92. The first controller 96and the second controller 97 can power the at least one motor 94 asshown in FIG. 10 or the at least one motor 94 with different drivingwindings (or poles) as shown in FIG. 12.

As shown in FIGS. 11 and 13, the first controller 96 can drive a firstmotor 98 and the second controller 97 can drive a second motor 99. Thefirst controller 96 and the second controller 97 can be flexible anddrive the first motor 98 or the second motor 99 depending on a switchingstate of a switch 101 as shown in FIG. 13. The first controller 96 andthe second controller 97 can be different. For example, the input DCvoltage of the first controller 96 and the second controller 97 from thefirst battery pack 91 and the second battery pack 92 can be different.However, the first controller 96 and the second controller 97 caninstead be identical.

The circuit 90 can select from at least two of the following connectionmodes. In a first connection mode, the first battery pack 91 can beelectrically connected over the controller 93 with the at least onemotor 94, while the second battery pack 92 may be electricallydisconnected from the at least one motor 94. In the first connectionmode, power can flow between the at least one motor 94 and the firstbattery pack 91, but may not flow between the at least one motor 94 andthe second battery pack 92. In a second connection mode, the secondbattery pack 92 can be electrically connected over the controller 93with the at least one motor 94, while the first battery pack 91 may beelectrically disconnected from the at least one motor 94. In the secondconnection mode, power can flow between the at least one motor 94 andthe second battery pack 92, but may not between the at least one motor94 and the first battery pack 91. In a third connection mode, the firstbattery pack 91 and the second battery pack 92 can be electricallyconnected over the controller 93 with the at least one motor 94. In thethird connection mode, power can flow between the at least one motor 94and the first battery pack 91 and the second battery pack 92. Electricalswitches can be used to perform this selection between differentconnection modes, and the electrical switches can be between thecontroller 93 and first battery pack 91 and the second battery pack 92,in the controller 93, or between the controller 93 and the at least onemotor 94. If the at least one motor 94 has more than one motor, therecan be further connection modes. The first battery pack 91 can beconnected with the first motor 98 and not the second motor 99 (fourthconnection mode) or with the second motor 99 and not the first motor 98(fifth connection mode) or with the first motor 98 and the second motor99 (sixth connection mode). The second battery pack 92 can be connectedwith the first motor 98 and not the second motor 99 (seventh connectionmode) or with the second motor 99 and not the first motor 98 (eighthconnection mode) or with the first motor 98 and the second motor 99(ninth connection state). The first battery pack 91 and the secondbattery pack 92 can be connected with the first motor 98 and not thesecond motor 99 (tenth connection mode) or with the second motor 99 andnot the first motor 98 (eleventh connection mode) or with the firstmotor 98 and the second motor 99 (twelfth connection state). Thenumbering of the connection modes can be arbitrarily chosen. If theremay additionally be a third battery pack, there can be correspondinglymore potential connection modes between the at least one motor and thethree battery packs.

The circuit 90 can select from at least two of the following drivemodes. In a first drive mode, the at least one motor 94 can be driven bythe first battery pack 91 (without using the power of the second batterypack 92). In this first drive mode (which may be referred to as astandard drive mode), the circuit 90 can be in the first connectionmode. Alternatively, in the first drive mode, the circuit 90 can also bein the third connection mode, while no power flows from the secondbattery pack 92 to the at least one motor 94. This standard drive modecan be used when the power consumption of the least one motor 94 may below, such as during steady flight conditions, gliding flight, or landingof an aircraft. In a second drive mode (which may be referred to as ahigh energy drive mode), the at least one motor 94 can be driven by thesecond battery pack 92 (without using the power of the first batterypack 91). In this second drive mode, the circuit 90 can be in the secondconnection mode. Alternatively, in the second drive mode, the circuit 90can also be in the third motor connection mode, while no power flowsfrom the first battery pack 91 to the at least one motor 94. This seconddrive mode can be used when the power consumption of the at least onemotor 94 may be high, such as during maneuvering, climb flight, or takeoff. In a third drive mode (which may be referred to as a very highenergy drive mode), the at least one motor 94 can be simultaneouslydriven by the first battery pack 91 and the second battery pack 92. Inthis third drive mode, the circuit 90 can be in the third connectionmode. This third drive mode can be used when the power consumption ofthe least one motor 94 may be high, such as during maneuvering, climbflight, or take off.

The circuit 90 can include a detector for detecting the powerrequirements of a present flight mode. The detection can be performedfrom user input or sensor measurements, such as by measuring the currentin the motor input line. The circuit 90 can select the drive mode or theconnection mode based at least on the detection result of this detector.

The selection between connection modes can depend at least on thecharging level of the different battery packs. For example, a high-powerbattery pack can be used instead, or in addition to, a highenergy-density battery pack when the charge of the high energy-densitybattery pack is low.

The electrical powering systems of FIGS. 8 to 13 can be configured suchthat the second battery pack 92 can be charged from the first batterypack 91, such as via the circuit 90. Moreover, the electrical poweringsystems can be configured such that the second battery pack 92 can becharged from the first battery pack 91 while the first battery pack 91powers or drives the at least one motor 94.

In FIGS. 9 to 11, the circuit 90 can electrically connect the firstbattery pack 91 and the second battery pack 92 for charging. Theconnection can be steady or realized by a switch which switches betweena first battery connection mode in which the first battery pack 91 andthe second battery pack 92 are electrically connected and a secondbattery connection mode in which the first battery pack 91 and thesecond battery pack 92 are electrically disconnected. As explainedfurther herein, the first battery connection mode can be realized byconnecting the first battery pack 91 and the second battery pack 92 overa charging circuit 95 or over the controller 93 or over one or moreother controllers.

In FIG. 9, the circuit 90 the charging circuit 95 for charging thesecond battery pack 92 from the first battery pack 91. The chargingcircuit 95 can control energy flow from the first battery pack 91 to thesecond battery pack 92 and may transfer the energy without transferringthe energy through the controller 93. The charging circuit 95 caninclude a switch (not shown) for connecting the first battery pack 91with the second battery pack 92 for charging. Such a switch may have theadvantage that the charging process can be controlled by a user or by amicroprocessor. For example, if the full power of the first battery pack91 is desired to power the at least one motor 94, the process ofcharging the second battery pack 92 may automatically be interrupted.However, the charging circuit 95 can instead work switchless so that theprocess of charging automatically starts when a certain electricalparameter, like the voltage or capacitance of the second battery pack92, falls below a certain threshold.

If the voltage of the first battery pack 91 and the second battery pack92 may be different, the charging circuit 95 can include a DC/DCconverter for converting the DC voltage of the first battery pack 91into the DC voltage of the second battery pack 92. The second batterypack 92 can be charged from the first battery pack 91 at the same timethat the at least one motor 94 is driven by the first battery pack 91 orat a time that the at least one motor 94 is not powered, such as by thefirst battery pack 91.

In FIG. 10, the second battery pack 92 can be charged over the firstcontroller 96 and the second controller 97. The first battery pack 91can provide energy and power for the first controller 96, which canconvert this energy and power into the electrical driving signals forthe at least one motor 94. For charging the second battery pack 92, theelectrical driving signals from the first controller 96 can be convertedby the second controller 97 into the charging signal (DC voltage) forthe second battery pack 92. The electrical driving signals for the atleast one motor 94 from the first controller 96 can be used for chargingthe second battery pack 92 and for driving the at least one motor 94 atthe same time. This can allow the second battery pack 92 to charge fromthe first battery pack 91 at the same time that the at least one motor94 may be driven by the electrical driving signals from the firstcontroller 96. The second battery pack 92 can however instead be chargedby the electrical drive signals without powering the motor at the sametime.

Instead of or in addition to electrically connecting the first batterypack 91 with the second battery pack 92 for transferring electricalenergy from the first battery pack 91 to the second battery pack 92, thefirst battery pack 91 can be mechanically connected with the secondbattery pack 92 for transferring mechanical energy to charge the secondbattery pack 92 from the first battery pack 91.

In FIG. 11, mechanical charging can be realized by driving the firstmotor 98 from the first battery pack 91 (over the first controller 96)and generating energy from the second motor 99 which is mechanicallyconnected to the first motor 98 and working as generator. The energygenerated by the second motor 99 can be used to charge the secondbattery pack 92 (by converting the generated motor signals of the secondmotor 99 via the second controller 97 into the charging signal (DCvoltage) of the second battery pack 92). This can allow the secondbattery pack 92 to charge from the first battery pack 91 at the sametime that the at least one motor 94 is driven by the energy from thefirst battery pack 91.

In FIG. 12, mechanical charging can be realized by driving the at leastone motor 94 from the first battery pack 91 (such as over the firstcontroller 96) with the first set of windings of the at least one motor94 and generating energy from the at least one motor 94 over the secondset of windings of the at least one motor 94 which can function as agenerator. The energy generated by the second set of windings can beused to charge the second battery pack 92 by converting the generatedmotor signals of the at least one motor 94 via the second controller 97into the charging signal (DC voltage) of the second battery pack 92.This can allow the second battery pack 92 to charge from the firstbattery pack 91 at the same time that the at least one motor 94 isdriven by the energy from the first battery pack 91. Moreover, this canenable the second battery pack 92 to charge from the first battery pack91 without utilizing separate circuitry, such as a DC/DC converter,which would increase a weight of the aircraft.

FIG. 13 shows a switch 101 which can select from different battery packsor connection modes as described herein. This can allow the firstbattery pack 91 to connect with the second battery pack 92 (firstbattery connection mode) to charge the second battery pack 92 directlyfrom the first battery pack 91. This can allow the first battery pack 91to connect with (i) one of the first controller 96 or the secondcontroller 97, (ii) one of the first motor 98 or second motor 99 and thesecond battery pack 92 with the other of the first controller 96 or thesecond controller 97, or (iii) the first motor 98 and the second motor99 to charge the second battery pack 92 mechanically. This can allow forselection of the first motor 98 or the second motor 99 to be driven bythe first battery pack 91 or the second battery pack 92.

The design of FIG. 13 can give the flexibility to choose amongelectrical charging or mechanical charging.

The second battery pack 92 can be charged by the at least one motor 94which can work as a generator. When the at least one motor 94 may workas a generator, the generation can be driven by braking energy, such asduring descent or landing of the aircraft. The second battery pack 92can as a result recover energy without affecting the functioning of thefirst battery pack 91 for long distances. When the at least one motor 94may work as a generator, the generation can be driven from the firstbattery pack 91 to charge the second battery pack 92. The second batterypack 92 can be charged by the at least one motor 94 working as agenerator while the same motor or another motor of the at least onemotor 94 can be driven by the energy from the first battery pack 91,such as for instance described with respect to FIGS. 11, 12, and 13.

The electrical powering system can include a third battery pack (notshown). The second battery pack 92 and the third battery pack can havedifferent electrical characteristics. The second battery pack 92 can,for instance, have a higher energy capacity than the third battery pack.The second battery pack 92 can have a higher energy density than thethird battery pack. The second battery pack 92 can have a lower maximum,nominal, or peak power than the third battery pack. The second batterypack 92 can have a lower maximum, nominal, or peak current than thethird battery pack. The second battery pack 92 can have a lower maximum,nominal, or peak voltage than the third battery pack. The type or thematerial composition of the battery cells of the second battery pack 92and the third battery pack can be different or the same. The thirdbattery pack can include a supercapacitor. The third battery pack canincrease a maximum power that may be delivered or recovered by theelectrical powering system. The power recovered by the at least onemotor 94 acting as a generator from a braking action can, for example,immediately be recovered in the third battery pack up to a high recoverpower level. The third battery pack can be charged from the firstbattery pack 91 or the second battery pack 92, such as even while the atleast one motor 94 may be driven from the power of the first batterypack 91 or the second battery pack 92.

Modular Battery System

The power sources in an electric or hybrid aircraft can be modular anddistributed to optimize a weight distribution or select a center ofgravity for the electric or hybrid aircraft, as well as maximize a useof space in the aircraft. Moreover, the batteries in an electric orhybrid aircraft can desirably be designed to be positioned in place of acombustion engine so that the aircraft can retain a similar shape orstructure to a traditional combustion powered aircraft and yet may bepowered by batteries. In such designs, the weight of the batteries canbe distributed to match that of a combustion engine to enable theelectric or hybrid aircraft to fly similarly to the traditionalcombustion powered aircraft.

FIG. 14A illustrates a battery module 1400 usable in an aircraft, suchas the aircraft 100 of FIGS. 1A and 1B. The battery module 1400 caninclude a lower battery module housing 1410, a middle battery modulehousing 1420, an upper battery module housing 1430, and a multiplebattery cells 1440. The multiple battery cells 1440 can together provideoutput power for the battery module 1400. The lower battery modulehousing 1410, the middle battery module housing 1420, or the upperbattery module housing 1430 can include slots, such as slots 1422, thatare usable to mechanically couple the lower battery module housing 1410,the middle battery module housing 1420, or the upper battery modulehousing 1430 to one another or to another battery module. Supports, suchas supports 1424 (for example, pins or locks), can be placed in theslots to lock the lower battery module housing 1410, the middle batterymodule housing 1420, or the upper battery module housing 1430 to oneanother or to another battery module.

The battery module 1400 can be constructed so that the battery module1400 is evenly cooled by air. The multiple battery cells 1440 caninclude 16 total battery cells where the battery cells are eachsubstantially shaped as a cylinder. The lower battery module housing1410, the middle battery module housing 1420, or the upper batterymodule housing 1430 can be formed of or include plastic and, whencoupled together, have an outer shape substantially shaped as arectangular prism. The lower battery module housing 1410, the middlebattery module housing 1420, or the upper battery module housing 1430can together be designed to prevent a fire in the multiple battery cells1440 from spreading outside of the battery module 1400.

The battery module 1400 can have a length of L₁, a width of W, and aheight of H₁. The length of L₁, the width of W, or the height of H₁ caneach be 50 mm, 65 mm, 80 mm, 100 mm, 120 mm, 150 mm, 200 mm, 250 mm orwithin a range defined by two of the foregoing values or another valuegreater or less than the foregoing values.

FIG. 14B illustrates an exploded view of the battery module 1400 of FIG.14A. In the exploded view, a plate 1450 and a circuit board assembly1460 of the battery module 1400 is shown. The plate 1450 can be copperand may electrically connect the multiple battery cells 1440 in parallelwith one another. The plate 1450 may also distribute heat evenly acrossthe multiple battery cells 1440 so that the multiple battery cells 1440age at the same rate. The circuit board assembly 1460 may transfer powerfrom or to the multiple battery cells 1440, as well as include one ormore sensors for monitoring a voltage or a temperature of one or morebattery cells of the multiple battery cells 1440. The circuit boardassembly 1460 may or may not provide galvanic isolation to the batterymodule 1400 with respect to any components that may be electricallyconnected to the battery module 1400. Each of the multiple battery cells1440 can have a height of H₂, such as 30 mm, 50 mm, 65 mm, 80 mm, 100mm, 120 mm, 150 mm or within a range defined by two of the foregoingvalues or another value greater or less than the foregoing values.

FIG. 15A illustrate a power source 1500A formed of multiple batterymodules 1400 of FIGS. 14A and 14B. The multiple battery modules 1400 ofthe power source 1500A can be mechanically coupled to one another. Afirst side of one battery module 1400 can be mechanically coupled to afirst side of another battery module 1400, and a second side of the onebattery module 1400 that is opposite the first side can be mechanicallycoupled to a first side of yet another battery module 1400. The multiplebattery modules 1400 of the power source 1500A can be electricallyconnected in series with one another. As illustrated in FIG. 15A, thepower source 1500A can include seven of the battery modules 1400connected to one another. The power source 1500A may, for example, havea maximum power output between 1 kW and 60 kW during operation, amaximum voltage output between 10 V and 120 V during operation, or amaximum current output between 100 A and 500 A during operation.

The power source 1500A can include a power source housing 1510mechanically coupled to at least one of the battery modules. The powersource housing 1510 can include an end cover 1512 that covers a side ofthe power source housing 1510. The power source housing 1510 can have alength of L₂, such as 3 mm, 5 mm, 10 mm, 15 mm, 20 mm, 25 mm, 30 mm, 40mm, 50 mm or within a range defined by two of the foregoing values oranother value greater or less than the foregoing values. The width andthe height of the power source housing 1510 can match the length of L₁and the width of W of the battery module 1400.

The power source 1500A can include power source connectors 1520. Thepower source connectors 1520 can be used to electrically connect thepower source 1500A to another power source, such as another of the powersource 1500A.

FIG. 15B illustrates a power source 1500B that is similar to the powersource 1500A of FIG. 15A but with the end cover 1512 and the upperbattery module housings 1430 of the battery modules 1400 removed.Because the end cover 1512 has been removed, a circuit board assembly1514 of the power source 1500B is now exposed. The circuit boardassembly 1514 can be electrically coupled to the battery modules 1400.The circuit board assembly 1514 can additionally provide galvanicisolation (for instance, 2500 Vrms) for the power source 1500B withrespect to any components that may be electrically connected to thepower source 1500B. The inclusion of galvanic isolation in this mannermay, for instance, enable grouping of the battery modules 1400 togetherso that isolation may be provided to the grouping of the battery modules1400 rather than individual modules of the battery modules 1400 or asubset of the battery modules 1400. Such an approach may reduce thecosts of construction because isolation can be expensive, and a singleisolation may be used for multiple of the battery modules 1400.

FIG. 16 illustrates a group 1600 of multiple power sources 1500A of FIG.15A arranged and connected for powering an aircraft, such as theaircraft 100 of FIGS. 1A and 1B. The multiple power sources 1500A of thegroup 1600 can be mechanically coupled to or stacked on one another. Themultiple power sources 1500A of the group 1600 can be electricallyconnected in series or parallel with one another, such as by a firstconnector 1610 or a second connector 1620 that electrically connects thepower source connectors 1520 of two of the multiple power sources 1500A.As illustrated in FIG. 16, the group 1600 can include 10 power sources(for instance, arranged in a 5 row by 2 column configuration). In otherexamples, a group may include a fewer or greater number of powersources, such as 2, 3, 5, 7, 8, 12, 15, 17, 20, 25, 30, 35, or 40 powersources.

The grouping of the multiple power sources 1500A to form the group 1600or another different group may allow for flexible configurations of themultiple power sources 1500A to satisfy various space or powerrequirements. Moreover, the grouping of the multiple power sources 1500Ato form the group 1600 or another different group may permit relativelyeasy or inexpensive replacement of one or more of the multiple powersources 1500A in the event of a failure or other issue.

FIG. 17A illustrates a perspective view of a nose 1700 of an aircraft,such as the aircraft 100 of FIGS. 1A and 1B, that includes multiplepower sources 1710, such as multiple of the power source 1500A, forpowering a motor 1720 that operates a propeller 1730 of the aircraft.The multiple power sources 1710 can be used to additionally oralternatively power other components of the aircraft. The multiple powersources 1710 can be sized and arranged to optimize a weight distributionand use of space around the nose 1700. The motor 1720 and the propeller1730 can be attached to and supported by a frame of the aircraft bysupports, which can be steel tubes, and connected by multiple fasteners,which be bolts with rubber shock absorbers. A firewall 1740 can providebarrier between the multiple power sources 1710 and the frame of theaircraft in the event of a first at the multiple power sources 1710. Anenclosure composed of glass fiber, metal, or mineral composite can bearound the multiple power sources 1710 to protect from water, coolant,or fire.

FIG. 17B illustrates a side view of the nose 1700 of FIG. 17A.

FIG. 18A illustrates a top view of a wing 1800 of an aircraft thatincludes multiple power sources 1810, such as multiple of the powersource 1500A, for powering one or more components of the aircraft. Themultiple power sources 1810 can be sized and arranged to optimize aweight distribution and use of space around the wing 1800. For example,the multiple power sources 1810 can be positioned within, between, oraround horizontal support beams 1820 or vertical support beams 1830 ofthe wing 1800. A relay 1840 can further be positioned in the wing 1800as illustrated and housed in a sealed enclosure. The relay 1840 may openif there is not a threshold voltage on a breaker panel or if a pilotopens breakers to shut down the multiple power sources 1810.

FIG. 18B illustrates a perspective view of the wing 1800 of FIG. 18A.

Multi-Coil Motor Control

An electric or hybrid aircraft can be powered by a multi-coil motor,such as an electric motor, in which different coils of the motor powerdifferent phases of a modulation cycle for the motor.

As can be seen from FIG. 19, a motor 1910 can include four differentfield coils (sometimes also referred to as coils) for generating atorque on a rotor of the motor 1910. The different field coils caninclude a first field coil 1902, a second field coil 1904, a third fieldcoil 1906, and a fourth field coil 1908. Each of the different fieldcoils can be independently powered by one or more controllers. The firstfield coil 1902, the second field coil 1904, the third field coil 1906,and the fourth field coil 1908 can be respectively powered by a firstcontroller 1912, a second controller 1914, a third controller 1916, anda fourth controller 1918. One or more of the first controller 1912, thesecond controller 1914, the third controller 1916, and the fourthcontroller 1918 may be the same controller.

The first controller 1912, the second controller 1914, the thirdcontroller 1916, and the fourth controller 1918 can vary a currentprovided to individual coils of the first field coil 1902, the secondfield coil 1904, the third field coil 1906, and the fourth field coil1908 to compensate for a failure of one or more (such as, one, two, orthree) of the field coils. The first controller 1912, the secondcontroller 1914, the third controller 1916, and the fourth controller1918 may, for example, no longer provide current to a coil that hasfailed and provide additional current to one or more coils that have notyet failed. The first controller 1912, the second controller 1914, thethird controller 1916, and the fourth controller 1918 can attempt tomaintain a power output of the motor (for example, above a threshold)despite the failure of the one or more of the field coils.

The first controller 1912, the second controller 1914, the thirdcontroller 1916, or the fourth controller 1918 can determine the failureof one or more of the field coils from one or more sensors monitoringthe motor or one or more individual field coils, such as proximate tothe motor or one or more individual field coils. The one or more sensorscan include a temperature sensor, a current sensor, or a magnetic fieldsensor, among other types of sensors. For example, where the one or moresensors includes at least one temperature sensor, the first controller1912, the second controller 1914, the third controller 1916, or thefourth controller 1918 can determine the failure of one or more of thefield coils from a change in the temperature sensed by the temperaturesensor (for instance, a temperature drop over time or proximatedifferent field coils may correspond to a failure of a particular fieldcoil or a number of field coils in the motor 1910). The first controller1912, the second controller 1914, the third controller 1916, or thefourth controller 1918 may moreover attempt to operate the motor so thatthe temperature sensed remains constant within a tolerance. As anotherexample, where the one or more sensors includes at least one voltagesensor, the first controller 1912, the second controller 1914, the thirdcontroller 1916, or the fourth controller 1918 can determine the failureof one or more of the field coils from a change in the voltage sensed bythe voltage sensor (for instance, a voltage spike may correspond to afailure of a particular field coil or a number of field coils in themotor 1910). As yet another example, where the one or more sensorsincludes at least one magnetic field sensor, the first controller 1912,the second controller 1914, the third controller 1916, or the fourthcontroller 1918 can determine the failure of one or more of the fieldcoils from a change in the resonance sensed by the magnetic fieldsensor.

FIG. 20 illustrates a process 2000 for operating a motor, such as themotor 1900, to compensate for the failure of a field coil of the motor.For convenience, the process 2000 is described as being performed by thefirst controller 1912, the second controller 1914, the third controller1916, or the fourth controller 1918 of FIG. 19. However, the process2000 may additionally or alternatively be performed by another processoror electronic circuitry, such as is described herein. The process 2000can advantageously enable a quick reaction (for instance, within a fewseconds or even faster) to failure of one or more failed field coils sothat the operation of the motor may be quickly adjusted to maintain apower output of the motor despite the failure of the one or more fieldcoils.

At block 2002, a failure of a field coil of a motor can be detected. Forexample, the first controller 1912, the second controller 1914, thethird controller 1916, or the fourth controller 1918 can detect failureof one or more of the first field coil 1902, the second field coil 1904,the third field coil 1906, or the fourth field coil 1908 from a changein electrical coil characteristics, a change in how the field coil maybe driven, a feedback from the motor 1900 about its operations, a changein performance of the motor 1900, or an output from a sensor.

At block 2004, a parameter can be set to indicate the failure of thefield coil. For instance, the first controller 1912, the secondcontroller 1914, the third controller 1916, or the fourth controller1918 can set a parameter in a memory device indicative of the failure ofthe field coil.

At block 2006, a driving of the motor can be modulated according to theparameter. For example, the first controller 1912, the second controller1914, the third controller 1916, or the fourth controller 1918 canadjust how the field coil that has failed is driven based on a storedindication that the field coil has failed. The first controller 1912,the second controller 1914, the third controller 1916, or the fourthcontroller 1918 may modulate a power input to the motor over time tocompensate for the failure of the field coil and, during a modulationcycle for the motor, to increase the power input to one or morefunctioning field coils to compensate for the failure.

The first controller 1912, the second controller 1914, the thirdcontroller 1916, or the fourth controller 1918 can, prior to a failureof a field coil, provide the electrical current one time to all of thefirst field coil 1902, the second field coil 1904, the third field coil1906, and the fourth field coil 1908 in an order prior to providing theelectrical current another time to any of the first field coil 1902, thesecond field coil 1904, the third field coil 1906, and the fourth fieldcoil 1908. Subsequent to the failure of the field coil, the firstcontroller 1912, the second controller 1914, the third controller 1916,or the fourth controller 1918 may no longer provide electrical currentto the field coil that has failed and can increase a current provided toone or more other field coils (such as to a field coil before the failedfield coil and after the failed field coil in the order) to compensatefor the failure of the field coil.

Additionally or alternatively, the electric or hybrid aircraft can varya rotation rate (for instance, revolutions per minute) of the motor or apitch of a propeller of the aircraft (for instance, increase the pitchto increase the power output) to compensate for a failure of one or more(such as, one, two, or three) of the field coils, as well as attempt tomaintain a power output of the motor despite the failure of the one ormore of the field coils.

Moreover, the process 2000 can be adjusted so that the driving of themotor may be modulated responsive to the detection of the failure of thefield coil and without the storing or referencing of the parameter.

Example Implementations

A battery monitoring system is disclosed for monitoring and transmittingparameters relating to the state of a battery pack to a driver or pilotof an electric vehicle. The battery monitoring system can include afirst battery monitoring circuit and a second redundant batterymonitoring circuit. The first battery monitoring circuit can includemultiple battery management systems (BMSs). Each BMS can manage andmonitor a different subset of battery cells in the battery pack. Thefirst battery monitoring circuit can include a digital communication busto provide first warning signals to a driver or pilot of the vehicle incase of dysfunction of the battery pack. The second battery monitoringcircuit can redundantly monitor the battery pack to provide at least onesecond warning signal to the driver or pilot of the vehicle in case ofdysfunction of the battery pack. The second battery monitoring circuitmay include only analog or combinational logic electronic components.

The battery monitoring system of the preceding paragraph can include oneor more of the following features: The second battery monitoring circuitcan be a processorless circuit. The second battery monitoring circuitmay include only analog or combinational logic electronic components.The second battery monitoring circuit may transmit only analog or binarysignals. The second battery monitoring circuit can transmit signals forthe driver or pilot via communications lines different from the digitalcommunication bus. The second battery monitoring circuit may not managethe charge and discharge of battery cells. The first battery monitoringcircuit can include first electronic measurement components and thesecond battery monitoring circuit can include second, distinctelectronic measurement components. The first electronic measurementcomponents can measure the temperature of battery cells, and the secondelectronic measurement components can measure the temperature of thesame battery cells. The first electronic measurement components candetect an undervoltage or overvoltage condition of battery cells, andsecond electronic measurement components can detect an undervoltage orovervoltage condition of the same battery cells. The first batterymonitoring circuit and the second battery monitoring circuit can share acommon set of electronic measurement components for measuring the stateof the battery cells. The second battery monitoring circuit can include:multiple identical BMS, each BMS controlling and monitoring one batterycell in the battery pack; and multiple master circuits, each mastercircuit controlling multiple BMS and collecting parameters monitored bythe multiple BMS circuits. Each master circuit can include a CAN busdriver circuit. The second battery monitoring circuit can includemultiple parameter sensors, each sensor generating one or a plurality ofdigital binary parameters depending on the state of one battery cell.The battery monitoring system can further include multiple combinationallogic components for combining multiple binary parameters related to onebattery cell. The battery monitoring system can further include multiplecombinational logic components for combining multiple binary parametersrelated to multiple battery cells and generating the at least one secondwarning signal if one of the battery cells is defect. The batterymonitoring system can further include multiple printed circuit board(PCB) cards, and one master circuit and one combinational logiccomponent can be mounted on each of the PCB cards. The second batterymonitoring circuit can be built so that any defective electronicmeasurement component triggers a second warning signal.

An electrical powering system is disclosed that can be used in anelectric aircraft for powering a driving thrust-generating propeller ora lift-generating rotor. The electrical powering system can include: atleast one motor; a first battery pack including high energy-density, lowpower battery cells; a second battery pack including low energy-density,high power battery cells; a circuit including a controller for poweringsaid at least one motor from at least one of said battery packs and forgenerating motor driving signals for driving said at least one motor;wherein the electrical powering system is configured to charge saidsecond battery pack from said first battery pack.

The electrical powering system of the preceding paragraph can includeone or more of the following features: The can charge said secondbattery pack from said first battery pack. The controller or the circuitcan transmit power from the first battery pack to the at least one motorat first instants and to the second battery pack and optionally to themotor at second instants. The controller or the circuit can include aselector for selecting a powering of the at least one motor: from thefirst battery pack only; from the second battery pack only; orsimultaneously from the first and from the second battery pack. Thecircuit can include a DC-DC converter for converting current from thefirst battery-pack into current for charging the second battery pack.The electrical powering system can further include: a first said motorand a second said motor; a first controller circuit for generating motordriving signals for driving the first said motor; a second controllercircuit for generating motor driving signals for driving the second saidmotor. The electrical powering system can further include a switchingmodule connected to said first battery pack, to said second batterypack, to said first controller, and to said second controller, forcommuting current from the first battery pack either, at differentinstants, to the second battery pack, to the first controller, or to thesecond controller. The switching module can commute current from thesecond battery pack either at different instants to the first controlleror to the second controller. At least one of said motors acting as agenerator for charging one of said battery packs. The electricalpowering system can further include a commutator for determining whichof said first battery pack and said second battery pack is charged bysaid generator. Said first battery pack and said second battery pack caninclude Li-Ion or Li-Po battery cells. The electrical powering systemcan further include a supercapacitor for powering said at least onemotor, wherein said circuit is able to power said at least one motorfrom at least one of said first battery pack and said second batterypack or from said supercapacitor, and to charge said second battery packfrom said first battery pack or from said supercapacitor. At least oneof said at least one motor is able to work as a generator, said circuitbeing arranged for charging one of said first battery pack and saidsecond battery pack from said generator when said generator isgenerating current. The electrical powering system can further includeone motor arranged to work at least during some instants as a motorpowered by one battery pack and as a generator for charging anotherbattery pack or supercapacitor. The electrical powering system canfurther two said motors on a single axis so that at least during someinstants one of the motors is functioning as a motor powered from onebattery pack while the other motor is functioning as a generator forcharging another battery pack. Aircraft can include the electricalpowering system.

An electrical powering system is disclosed that can be used in anelectric aircraft for powering a driving thrust-generating propeller ora lift-generating rotor. The electrical powering system can include: atleast one motor; a first battery pack including high energy-density, lowpower battery cells; a second battery pack including low energy-density,high power battery cells; and a circuit comprising a controller forpowering said at least one motor from at least one of said battery packsand for generating motor driving signals for driving said at least onemotor. The electrical power system is configured to charge said firstbattery pack or said second battery pack from at least one of the atleast one motor operating as generator.

The electrical powering system of the preceding paragraph can includeone or more of the following features: The electrical powering systemcan charge said second battery pack from at least one of the at leastone motor operating as generator. The controller can include: a firstcontroller for powering said at least one motor from the first batterypack and for generating motor driving signals for driving said at leastone motor; and a second controller for charging the second battery packfrom the generator signals generated by the one motor operating asgenerator. The second controller can power said at least one motor fromthe second battery pack and for generating motor driving signals fordriving said at least one motor. The at least one motor can include anelectrical motor with a rotor, a first set of windings connected to thefirst controller for driving the rotor of the electrical motor based onthe signals from the first controller, and a second set of windingsconnected to the second controller for generating generator signals fromthe rotor of the electrical motor to charge the second battery pack. Theat least one motor can include a first motor connected to the firstcontroller for driving the first motor based on the signals from thefirst controller and a second motor connected to the second controllerfor generating generator signals from the second motor of the electricalmotor to charge the second battery pack. The first motor and the secondmotor can be mechanically coupled. The electrical powering system canconcurrently drive the at least one motor based on the first batterypack and charge the second battery pack from the motor operated asgenerator. The electrical powering system can further include asupercapacitor, and the electrical powering system can charge thesupercapacitor from the motor operated as generator. The circuit candrive the at least one motor in different drive modes, and the differentdrive modes can include a first drive mode in which the at least onemotor is driven from the energy of the first battery pack. The differentdrive modes can include at least one of the following: a drive mode inwhich the at least one motor is driven from the power of the firstbattery pack and of the second battery pack, a drive mode in which theat least one motor is driven from the power of the second battery pack,a drive mode in which the at least one motor is driven from the power ofthe first battery pack and in which the second battery pack is chargedby the power generated from the motor operated as generator, a drivemode in which the at least one motor is driven from the power of thefirst battery pack and in which the second battery pack is charged bythe power generated from the motor operated as generator, a drive modein which the first battery pack is charged by the power generated fromthe motor operated as generator, a drive mode in which the secondbattery pack is charged by the power generated from the motor operatedas generator, a drive mode in which the first battery pack and thesecond battery pack is charged by the power generated from the motoroperated as generator. The electrical powering system can furtherinclude a supercapacitor, and the different drive modes can include atleast one of the following: a drive mode in which the at least one motoris driven from the power of the supercapacitor, a drive mode in whichthe at least one motor is driven from the power of the supercapacitorand of the first or second battery pack, a drive mode in which the atleast one motor is driven from the power of the first battery pack orsecond battery pack and in which the super capacitor is charged by thepower generated from the motor operated as generator, a drive mode inwhich the supercapacitor is charged by the power generated from themotor operated as generator, a drive mode in which the supercapacitorand the first battery pack or the second battery pack is charged by thepower generated from the motor operated as generator. The second batterypack can be charged from the power of the first battery pack. Anaircraft can include the electrical powering system. The motor operatingas generator can be driven by braking energy of the aircraft.

Additional Features and Terminology

Although examples provided herein may be described in the context of anaircraft, such as an electric or hybrid aircraft, one or more featuresmay further apply to other types of vehicles usable to transportpassengers or goods. For example, the one or more futures can be used toenhance construction or operation of automobiles, trucks, boats,submarines, spacecrafts, hovercrafts, or the like.

As used herein, the term “programmable component,” in addition to havingits ordinary meaning, can refer to a component that may processexecutable instructions to perform operations or may be configured aftermanufacturing to perform different operations responsive to processingthe same inputs to the component. As used herein, the term“non-programmable component,” in addition to having its ordinarymeaning, can refer to a component that may not process executableinstructions to perform operations and may not be configured aftermanufacturing to perform different operations responsive to processingthe same inputs to the component.

As used herein, the term “stateful component,” in addition to having itsordinary meaning, can refer to a component that may remember a precedingstate or event prior to a current state or event. A stateful componentthus may determine an output from an event history as opposed to justfrom a current condition. As used herein, the term “non-statefulcomponent,” in addition to having its ordinary meaning, can refer to acomponent that may not remember a preceding state or event prior to acurrent state or event. A non-stateful component thus may not determinean output from an event history but may determine an output from acurrent condition.

Many other variations than those described herein will be apparent fromthis disclosure. For example, depending on the embodiment, certain acts,events, or functions of any of the algorithms described herein can beperformed in a different sequence, can be added, merged, or left outaltogether (for example, not all described acts or events are necessaryfor the practice of the algorithms). Moreover, in certain embodiments,acts or events can be performed concurrently, for instance, throughmulti-threaded processing, interrupt processing, or multiple processorsor processor cores or on other parallel architectures, rather thansequentially. In addition, different tasks or processes can be performedby different machines or computing systems that can function together.

The various illustrative logical blocks, modules, and algorithm stepsdescribed herein can be implemented as electronic hardware, computersoftware, or combinations of both. To clearly illustrate thisinterchangeability of hardware and software, various illustrativecomponents, blocks, modules, and steps have been described abovegenerally in terms of their functionality. Whether such functionality isimplemented as hardware or software depends upon the particularapplication and design constraints imposed on the overall system. Thedescribed functionality can be implemented in varying ways for eachparticular application, but such implementation decisions should not beinterpreted as causing a departure from the scope of the disclosure.

The various illustrative logical blocks and modules described inconnection with the embodiments disclosed herein can be implemented orperformed by a machine, a microprocessor, a state machine, a digitalsignal processor (DSP), an application specific integrated circuit(ASIC), a FPGA, or other programmable logic device, discrete gate ortransistor logic, discrete hardware components, or any combinationthereof designed to perform the functions described herein. A hardwareprocessor can include electrical circuitry or digital logic circuitryconfigured to process computer-executable instructions. In anotherembodiment, a processor includes an FPGA or other programmable devicethat performs logic operations without processing computer-executableinstructions. A processor can also be implemented as a combination ofcomputing devices, e.g., a combination of a DSP and a microprocessor, aplurality of microprocessors, one or more microprocessors in conjunctionwith a DSP core, or any other such configuration. A computingenvironment can include any type of computer system, including, but notlimited to, a computer system based on a microprocessor, a mainframecomputer, a digital signal processor, a portable computing device, adevice controller, or a computational engine within an appliance, toname a few.

The steps of a method, process, or algorithm described in connectionwith the embodiments disclosed herein can be embodied directly inhardware, in a software module stored in one or more memory devices andexecuted by one or more processors, or in a combination of the two. Asoftware module can reside in RAM memory, flash memory, ROM memory,EPROM memory, EEPROM memory, registers, hard disk, a removable disk, aCD-ROM, or any other form of non-transitory computer-readable storagemedium, media, or physical computer storage known in the art. An examplestorage medium can be coupled to the processor such that the processorcan read information from, and write information to, the storage medium.In the alternative, the storage medium can be integral to the processor.The storage medium can be volatile or nonvolatile. The processor and thestorage medium can reside in an ASIC.

Conditional language used herein, such as, among others, “can,” “might,”“may,” “e.g.,” and the like, unless specifically stated otherwise, orotherwise understood within the context as used, is generally intendedto convey that certain embodiments include, while other embodiments donot include, certain features, elements or states. Thus, suchconditional language is not generally intended to imply that features,elements or states are in any way required for one or more embodimentsor that one or more embodiments necessarily include logic for deciding,with or without author input or prompting, whether these features,elements or states are included or are to be performed in any particularembodiment. The terms “comprising,” “including,” “having,” and the likeare synonymous and are used inclusively, in an open-ended fashion, anddo not exclude additional elements, features, acts, operations, and soforth. Also, the term “or” is used in its inclusive sense (and not inits exclusive sense) so that when used, for example, to connect a listof elements, the term “or” means one, some, or all of the elements inthe list. Further, the term “each,” as used herein, in addition tohaving its ordinary meaning, can mean any subset of a set of elements towhich the term “each” is applied.

What is claimed is:
 1. An aircraft monitoring system for an electric or hybrid airplane, the aircraft monitoring system being constructed to enable the electric or hybrid aircraft to pass certification requirements relating to a safety risk analysis, the aircraft monitoring system having different subsystems for monitoring and alerting of failures of components of the electric or hybrid aircraft, the failures that pose a greater safety risk being monitored and indicated by one or more subsystems without use of programmable components, the aircraft monitoring system comprising: a first subsystem configured to be supported by a housing and consisting of non-programmable components, the housing being configured to fly and be propelled by an electric motor, wherein the non-programmable components are configured to: monitor a power source supported by the housing, the power source being configured to power the electric motor, and output a first alert to notify of a first condition associated with the power source, the first condition being likely to imminently cause a fatality or a destruction of the housing; and a second subsystem configured to be supported by the housing and comprising a processor and a communication bus, wherein the processor is configured to: monitor the power source from communications on the communication bus, and output a second alert to notify of a second condition associated with the power source.
 2. The aircraft monitoring system of claim 1, wherein the non-programmable components consist of analog or combinational logic electronic components.
 3. The aircraft monitoring system of claim 1, wherein the non-programmable components consist of non-stateful components.
 4. The aircraft monitoring system of claim 1, wherein any subsystem that is supported by the housing and configured to notify of catastrophic conditions is configured to monitor for the catastrophic conditions and notify of the catastrophic conditions without using programmable components or stateful components, the catastrophic conditions being likely to imminently cause the fatality or the destruction of the housing.
 5. The aircraft monitoring system of claim 1, wherein the non-programmable components are configured to activate an indicator supported by the housing to output the first alert, the indicator being configured to remain inactive unless the indicator is outputting the first alert.
 6. The aircraft monitoring system of claim 5, wherein the indicator comprises a light.
 7. The aircraft monitoring system of claim 5, wherein the indicator comprises an audible alarm.
 8. The aircraft monitoring system of claim 1, wherein the first subsystem is not configured to control the power source, and the second subsystem is configured to control the power source.
 9. The aircraft monitoring system of claim 1, wherein the first subsystem is configured to process analog signals and binary signals but not multivalued digital signals.
 10. The aircraft monitoring system of claim 1, further comprising a plurality of printed circuit boards, at least part of the first subsystem and at least part of the second subsystem being mounted on the plurality of printed circuit boards.
 11. The aircraft monitoring system of claim 1, wherein the first subsystem is not configured to communicate via the communication bus.
 12. The aircraft monitoring system of claim 1, wherein: the non-programmable components are configured to monitor the power source using a first output from a first sensor; and the processor is configured to monitor the power source using a second output from a second sensor different from the first sensor.
 13. The aircraft monitoring system of claim 12, wherein the first sensor and the second sensor are configured to detect a state of the power source.
 14. The aircraft monitoring system of claim 12, wherein the first sensor and the second sensor are configured to measure a temperature of the power source.
 15. The aircraft monitoring system of claim 12, wherein the first sensor and the second sensor are configured to detect an undervoltage condition, an overvoltage condition, an underpressure condition, an overpressure condition, an undercurrent condition, an overcurrent condition, an excessive internal resistance condition, a low internal resistance condition, a high temperature condition, or a low temperature condition of the power source.
 16. The aircraft monitoring system of claim 12, wherein the first sensor and the second sensor are configured to detect that the power source is on fire.
 17. The aircraft monitoring system of claim 1, wherein the non-programmable components are configured to output the first alert to the processor or another processor supported by the housing, and the processor or the another processor are configured to activate a component supported by the housing to attempt to address the first condition.
 18. The aircraft monitoring system of claim 1, wherein the non-programmable components are configured to output the first alert to an electronic device remote from the housing.
 19. The aircraft monitoring system of claim 1, wherein the non-programmable components and the processor are configured to monitor the power source using a common output from a sensor.
 20. The aircraft monitoring system of claim 1, wherein the second alert indicates that an amount of energy stored by the power source is below a threshold.
 21. The aircraft monitoring system of claim 1, wherein the power source comprises a battery.
 22. The aircraft monitoring system of claim 1, wherein the first condition is a failure or an overheating of the power source.
 23. The aircraft monitoring system of claim 1, wherein the first condition is the power source being on fire.
 24. The aircraft monitoring system of claim 1, wherein the first alert indicates that a crash of the housing is imminent.
 25. The aircraft monitoring system of claim 1, wherein the non-programmable components comprise an electronic device configured to process an analog signal.
 26. The aircraft monitoring system of claim 1, further comprising a display configured to present the second alert.
 27. A method of operating an aircraft monitoring system of an electric or hybrid airplane, the aircraft monitoring system being constructed to enable the electric or hybrid aircraft to pass certification requirements relating to a safety risk analysis, the method comprising: supporting a first subsystem and a second subsystem with a housing, the first subsystem consisting of non-programmable components, the second subsystem comprising a processor and a communication bus, the housing being configured to fly and be propelled by an electric motor; powering, by a power source supported by the housing, the electric motor; monitoring, by the non-programmable components, the power source; outputting, by the non-programmable components, a first alert to notify of a first condition associated with the power source, the first condition being likely to imminently cause a fatality or a destruction of the housing; monitoring, by the processor, the power source from communications on the communication bus; and outputting, by the processor, a second alert to notify of a second condition associated with the power source.
 28. The method of claim 27, further comprising: activating an indicator supported by the housing to output the first alert; inactivating the indicator when the non-programmable components are not outputting the first alert; and presenting the second alert on a display supported by the housing.
 29. The method of claim 27, wherein the non-programmable components monitor the power source using a first output from a first sensor, and the processor monitors the power source using a second output from a second sensor, and further comprising: by the first sensor and the second sensor, detecting an undervoltage condition, an overvoltage condition, an underpressure condition, an overpressure condition, an undercurrent condition, an overcurrent condition, an excessive internal resistance condition, a low internal resistance condition, a high temperature condition, or a low temperature condition associated with the power source.
 30. The method of claim 27, further comprising, responsive to the first alert, activating a component supported by the housing to attempt to address the first condition. 